Kaplan Pathology Flashcards
1
Q
1. Which of the following is the MOST likely explanation for when two days after removal of a cancerous neck lesion, there is thigh and calf cramps, tingling around the lips, low serum calcium, and high serum phosphate? A. Hyperparathyroidism B. Primary hypoparathyroidism C. Pseudohypoparathyroidism D. Renal failure E. Vitamin D deficiency
A
The correct answer is B. Surgically related hypoparathyroidism is the most common cause of
primary hypoparathyroidism. Exploration of the anterior neck during thyroidectomy,
parathyroidectomy, or removal of neck lesions can all compromise parathyroid gland function. Often
the problem occurs because the blood supply to the parathyroid glands is interrupted during the
surgery. The decrease in plasma parathyroid hormone leads to hypocalcemia and
hyperphosphatemia. The decreased serum calcium is caused by decreased absorption of dietary
calcium (because vitamin D activation is decreased) and decreased movement of calcium from bone
to extracellular fluid. Low serum calcium can lead to tetany and paresthesias because of
destabilization of excitable tissue membranes. Tetany is most often observed when there is a rapid
decrease in serum calcium, such as that occurring with surgical hypoparathyroidism. The increased
serum phosphate is caused by decreased renal excretion.
Hyperparathyroidism (choice A) is frequently asymptomatic; however, renal stones, polyurine,
hypertension, constipation, fatigue, and mental status changes may be seen. Serum and urine
calcium is elevated. Urine phosphate is high and a low to normal serum phosphate is generally seen.
Pseudohypoparathyroidism (choice C) is a rare genetic defect in which the target tissues are
insensitive to parathyroid hormone. Because parathyroid hormone is less effective, serum calcium
decreases and serum phosphate increases. Pseudohypoparathyroidism is also accompanied by
developmental defects, including mental retardation, short stature, and missing metatarsal or
metacarpal bones.
In renal failure (choice D), hyperphosphatemia occurs because of decreased renal excretion. This
can lead to hypocalcemia as the equilibrium between serum phosphate and serum calcium is pushed
toward hydroxyapatite. Furthermore, dietary absorption of calcium is decreased because vitamin D
activation is decreased by hyperphosphatemia, even before there is significant decrease in renal 1-
alpha-hydroxylase activity. The low serum calcium produces a compensatory increase in parathyroid
hormone with subsequent bone demineralization (renal osteodystrophy).
With vitamin D deficiency (choice E), serum calcium and phosphate are typically decreased. The
calcium is low because of decreased dietary absorption. The phosphate is low (not high) because of
decreased dietary absorption, and because the secondary increase in parathyroid hormone secretion
(caused by the hypocalcemia) increases renal excretion of phosphate.
2
Q
- At what level in the skin do bullae MOST likely develop in a localized cutaneous infection
around the mouth with phage group II Staphylococcus aureus?
A. Across the basal cells
B. Below the basement membrane
C. Between the basal cells and the basement membrane
D. High in the epidermis
E. Just above the basal cells
A
The correct answer is D. Bullous diseases of the skin are subdivided on the basis of the level at
which the cleavage for blister formation occurs. In general, the lower in the epidermis/dermis that the
cleavage plane occurs, the more dangerous and widespread the blistering. This is because blistering
at lower levels, particularly those involving the basal cell layer, permits loss of substantial amounts of
fluid and heals slowly (often with significant scarring). Scalded-skin syndrome (toxic epidermal
necrolysis) may follow staphylococcal (often phage group II) skin infection. This disorder fortunately
involves the very superficial squamous cells just beneath the granular layer. Consequently, the
disease (which typically produces bright red skin sloughing) usually resolves without sequelae after
antibiotic therapy. “Scalded-skin” may also be observed in association with drug-induced erythema
multiforme. Major inciting agents include phenylbutazones, sulfonamides, barbiturates,
aminopenicillins, oxicam, nonsteroidal antiinflammatory agents, and allopurinol. This form usually
affects the mucosa (eyes, mouth) first, and is much more dangerous because the blistering is
subepidermal, and the entire overlying epidermis becomes necrotic.
3
Q
- Which of the following cell types show abnormal function when there is a history in a young
adult of multiple arm and leg fractures following minor falls, with a slight weakness of facial
muscles on the left, mild anemia, and with generalized bony widening with partial obliteration
of marrow spaces?
A. Granulocytic stem cells
B. Megakaryocytes
C. Plasma cells
D. Osteoblasts
E. Osteoclasts
A
The correct answer is E. The disease described is osteopetrosis (Albers-Schonberg disease), which
is a group of hereditary diseases in which impaired osteoclast function leads to reduced bone
resorption. The abnormal osteoclasts frequently are enlarged, with bizarre shapes. The bones
become thick and brittle; other features include anemia secondary to marrow loss and cranial nerve
deficits secondary to narrowing of bony ostea. An autosomal recessive, severe form of the disease
produces death in childhood. A relatively benign, autosomal dominant form presents in adulthood.
Abnormal proliferation of granulocytic stem cells (choice A) can produce myelocytic leukemias.
Megakaryocyte abnormalities (choice B) can produce platelet disorders, but not deficient bone
resorption.
In multiple myeloma, neoplastic plasma cells (choice C) can cause lytic bone lesions characterized
by excessive resorption of bone.
Abnormally low osteoclast, rather than osteoblast (choice D), function is the problem in osteopetrosis.
4
Q
- What of the following is characterized by left lower quadrant periumbilical pain in an elderly
person, with the presence of fever, tender abdomen, leukocytosis, nausea, and vomiting?
A. Acute appendicitis
B. Diverticulitis
C. Gallstones
D. Pancreatitis
E. Pyelonephritis
A
The correct answer is B. Diverticulitis is a disease of the elderly and usually involves the distal
colon. In severe cases, however, the diverticula may extend throughout the colon and up to the
cecum. Inflammation of a cecal diverticulum can closely mimic acute appendicitis. The essentials of
diagnosis for diverticulitis are acute abdominal pain and fever, left lower abdominal tenderness, and
mass. Leukocytosis is commonly present together with nausea and vomiting.
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Acute appendicitis (choice A) is usually a disease of young adults (and sometimes children). It is
rarely seen in the elderly.
Pancreatitis (choice D), pyelonephritis (choice E), and gall bladder disease (choice C), refer pain to
the mid back, lateral back, and right upper quadrant, respectively.
5
Q
- Which of the following genetic conditions is MOST likely to be the cause of a child born with
with a small head, small eyes, six fingers on each hand, and congenital heart defects?
A. Trisomy 13
B. Trisomy 18
C. Trisomy 21
D. XXY
E. XYY
A
The correct answer is A. This is a description of Patau’s syndrome or trisomy 13. This disorder is
also associated with severe mental retardation, abnormal forebrain structures, and death within 1 year
of birth. Patau’s syndrome has an incidence of 1:6,000 births, making it the second most common
form of autosomal trisomy.
Trisomy 18 (choice B) is Edwards syndrome, characterized by severe mental retardation, rocker
bottom feet (also sometimes seen in Patau’s syndrome), low-set ears, micrognathia, clenched hands,
prominent occiput, and death within 1 year. Edwards syndrome has an incidence of 1:8,000, making it
the third most common autosomal trisomy.
Trisomy 21 (choice C) is Down syndrome, and is characterized by mental retardation, flat facial
profile, prominent epicanthal folds, simian crease, duodenal atresia, and congenital heart disease.
Down syndrome is the most common autosomal trisomy, with an incidence of 1:700.
XXY (choice D) is Klinefelter’s syndrome and is associated with male hypogonadism and infertility,
eunuchoid body habitus, gynecomastia, and lack of male secondary sexual characteristics.
XYY (choice E) is double Y syndrome. Affected individuals often go undetected, but may be taller
than average and may be more likely to exhibit aggressive, antisocial behavior.
6
Q
- If a woman 22 weeks pregnant has ankle edema and proteinuria, the presence of which of
the following would determine if she has preeclampsia?
A. Diabetes mellitus
B. Hyperuricemia
C. Hypertension
D. Systemic lupus erythematosus
E. Thrombocytopenia
A
The correct answer is C. A pregnant patient is considered to be in preeclampsia if she develops
hypertension, proteinuria, and edema. The hypertension is defined as a sustained elevation of blood
pressure of 140 mm Hg systolic or 90 mm Hg diastolic or more in the absence of chronic hypertension
after 20 weeks’ gestation. Eclampsia includes the addition of seizures to the triad. Approximately 7%
of pregnant women develop preeclampsia, typically between 20 weeks’ gestation to 6 weeks
postpartum. Predisposing conditions include preexisting hypertension, diabetes (choice A), and
autoimmune diseases such as lupus (choice D). Laboratory features can include hyperuricemia
(choice B) and thrombocytopenia (choice E), but these are not used to define the presence of
preeclampsia.
7
Q
7. Which of the following blood components can be expected to increase with disseminated intravascular coagulation? A. Factor V B. Fibrin degradation products C. Fibrinogen D. Plasminogen E. Platelets
A
The correct answer is B. Disseminated intravascular coagulation (DIC or consumptive
coagulopathy) represents pathologic activation of the coagulation system by another underlying
disease, with consequent consumption and depletion of the cellular and humoral components of the
coagulation cascade. The fibrinolytic mechanisms are also activated, and an uncontrolled cycle of
bleeding and clotting develops. The essentials of diagnosis include underlying serious illness,
hypofibrinogenemia, thrombocytopenia, fibrin degradation products, and prolonged prothrombin time.
As a consequence, levels of all clotting proteins (choices A and C) become depleted, platelet counts
drop (choice E), and the fibrinolytic proteins are depleted also (choice D). Fibrin degradation
products (choice B), which are normally low in the serum, increase markedly because of increased
fibrinolysis seen in this disease; identification of these proteins can be an important indicator of DIC.
8
Q
- Which of the following additional clinical findings would MOST be associated with a woman
who has oral mucosal swelling, xerostomia, and intense salivary gland destructive
inflammation, as well as antibodies against ribonucleoprotein?
A. Conjunctivitis
B. Goiter
C. Hemolytic anemia
D. Proximal muscle weakness
A
The correct answer is A. This describes Sjogren’s syndrome, an autoimmune disease characterized
by dry eyes (keratoconjunctivitis) and a dry mouth (xerostomia) caused by destruction of the lacrimal
and salivary glands. Sjogren’s syndrome is also characterized by autoantibody production. The most
diagnostic autoantibodies are those against ribonucleoproteins.
Goiters (choice B) are not typical of Sjogren’s syndrome. Although autoimmune thyroiditis is
associated with Sjogren’s syndrome, ocular involvement is much more characteristic than thyroid
involvement.
Hemolytic anemia (choice C) is not characteristic of Sjogren’s syndrome. Primary autoantibodies,
drugs, and systemic lupus erythematosus may be associated with hemolytic anemia.
Proximal muscle weakness (choice D), in association with autoantibodies, is expected in polymyositis
or dermatomyositis. Although polymyositis may occur in association with Sjogren’s syndrome,
keratoconjunctivitis would be much more common than muscle weakness.
9
Q
- What phenomenon is responsible when a person sets off the metal detector at the airport,
despite removing watch, belt buckle, and every other obvious source of metal?
A. Argyria
B. Gall stones
C. Hemochromatosis
D. Kidney stones
E. Wilson’s disease
A
The correct answer is C. Hemochromatosis is an iron storage disorder that can cause cirrhosis (with
increased risk for hepatocellular carcinoma), skin pigmentation, pancreatic damage leading to
diabetes mellitus, and congestive heart failure. These complications are attributable to damage
caused by deposition of iron in tissues; the total body iron in some of these individuals may reach 50
g, sufficient to set off some airport metal detectors.
Argyria (choice A) is a blue-gray skin discoloration related to silver poisoning.
Neither gallstones (choice B) nor kidney stones (choice D) contain metal.
In Wilson’s disease (choice E), copper is deposited in the liver and brain, but not enough to be
detected by metal detectors.
10
Q
- Which of the following is the explanation for the laboratory findings in an alcoholic with
chronic obstructive lung disease, secondary to cigarette smoking, of persistently lower serum
levels than expected of theophylline which is being used as a bronchodilator, even though the
drug is taken according to schedule?
A. Cirrhosis of the liver
B. Decreased absorption
C. Enhanced liver metabolism
D. Increased urinary clearance
E. Noncompliance
A
The correct answer is C. Alcohol and smoking normally enhance the cytochrome P450 system in the
smooth endoplasmic reticulum (SER) of the liver. This system is responsible for the metabolism of
drugs, hence, the low theophylline levels are most likely caused by enhanced liver metabolism. The
hepatocyte SER undergoes hyperplasia as a response to alcohol ingestion and synthesizes the
enzyme gamma-glutamyl transferase (GGT). An elevation of GGT would help confirm the likelihood of
increased hepatic drug metabolism as the cause of low drug levels.
Cirrhosis of the liver (choice A) would likely increase the serum levels of theophylline because of poor
metabolism of the drug.
Decreased absorption of the drug (choice B) in the gastrointestinal tract is a possible choice. The
history of excess alcohol intake, chronic smoking, and lack of a history of malabsorption, however,
suggest increased hepatic metabolism.
Increased clearance of theophylline in the urine (choice D) implies an increase in the glomerular
filtration rate, which would not be expected in this patient.
In most circumstances, the lack of an expected response to a medication is because of patient
noncompliance until proven otherwise; however, the question stem rules this out.
11
Q
- Which of the following could develop with a mucosal neuroma on the lower lip, family
history of medullary thyroid carcinoma, and recent introduction of severe headaches,
perspiration, palpitations, and hypertension?
A. Gastrinoma
B. Insulinoma
C. Parathyroid adenoma
D. Pheochromocytoma
E. Pituitary adenoma
A
The correct answer is D. This describes multiple endocrine neoplasia, specifically, MEN III (formerly
MEN II b). Features of this autosomal dominant condition include medullary carcinoma of the thyroid,
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pheochromocytoma, and oral and intestinal ganglioneuromatosis (including mucosal neuromas).
Pheochromocytomas typically cause attacks of severe headache, perspiration, palpitations,
hypertension, anxiety, and tremor.
Gastrinomas (choice A) and insulinomas (choice B) are found in MEN I.
Parathyroid adenomas (choice C) are found in MEN I and II.
Pituitary adenomas (choice E) are found in MEN I.
12
Q
- Which of the following substances is significantly elevated in the serum of a young adult
male with bilateral parotid gland swelling, orchitis, and fever and malaise?
A. Alanine aminotransferase
B. Amylase
C. Aspartate aminotransferase
D. Cortisol
E. Creatine phosphokinase, MB isoenzyme
A
The correct answer is B. The disease described is mumps, caused by a paramyxovirus. In children,
mumps causes a transient inflammation of the parotid glands, and less commonly the testes,
pancreas, or central nervous system. Mumps tends to be a more severe disease in adults than in
children as it involves the testes (causing orchitis) and pancreas with some frequency. Pancreatic
involvement can cause elevation of serum amylase.
Alanine aminotransferase (ALT) (choice A) and Aspartate aminotransferase (AST) (choice C) are
markers for hepatocellular damage.
Cortisol (choice D) levels are increased in patients with Cushing’s syndrome. This condition is
associated with central obesity, muscle wasting, thin skin, easy bruisability, psychologic changes,
hirsutism, and purple stria. Osteoporosis, hypertension, hyperglycemia, and glycosuria are also noted.
Creatine phosphokinase, MB isoenzyme (CPK-MB) (choice E) is the isoenzyme of CPK that is
relatively specific for the myocardium. This enzyme is increased in the early stages of a myocardial
infarction.
13
Q
12. Which of the following forms of gastritis would MOST likely be found with a history of longterm use of nonsteroidal antiinflammatory drugs and complaints of heartburn, nausea, and vomiting for several days? A. Acute gastritis B. Chronic antral gastritis C. Chronic fundal gastritis D. Hypertrophic gastritis E. Lymphocytic gastritis
A
The correct answer is A. Acute gastritis, characterized by patches of erythematous mucosa,
sometimes with petechiae and ulceration, can be seen as a complication of a variety of other
conditions (alcohol use, aspirin and other NSAIDs use, smoking, shock, steroid use, and uremia),
which usually have in common disruption of the mucosal barrier of the stomach.
Chronic antral (type B) gastritis (choice B) is associated with Helicobacter pylori.
Chronic fundal (type A) gastritis (choice C) is associated with pernicious anemia.
6
Hypertrophic gastritis (Menetrier’s disease; choice D) is an idiopathic condition characterized by
markedly enlarged mucosal folds.
Lymphocytic gastritis (choice E) is believed to be a gastric manifestation of celiac sprue.
14
Q
13. What is responsible for mild temporary hyperthyroidism after a person complains of a severe sore throat? A. Diffuse nontoxic goiter B. Grave's disease C. Hashimoto's thyroiditis D. Subacute granulomatous thyroiditis
A
The correct answer is D. It is due to subacute granulomatous (de Quervain) thyroiditis, which
frequently develops after a viral infection. Microscopically, it is characterized by microabscess
formation within the thyroid, eventually progressing to granulomatous inflammation with
multinucleated giant cells. Clinically, patients may experience fever, sudden painful enlargement of
the thyroid, or symptoms of transient hyperthyroidism. The disease usually abates within 6-8 weeks.
Diffuse nontoxic goiter (choice A) by definition does not produce hyperthyroidism. Goiter is usually
associated with low thyroid function.
The hyperthyroidism of Grave’s disease (choice B) does not spontaneously remit.
Hashimoto’s thyroiditis (choice C) can cause transient hyperthyroidism, but then goes on to cause
hypothyroidism.
15
Q
- What reaction has occured if after receiving a tuberculosis vaccine, the area becomes
indurated and erythematous, having a 12 mm diameter?
A. Antibody-dependent cell-mediated cytotoxicity
B. Local anaphylaxis
C. T-cell mediated cytotoxicity
D. Type III hypersensitivity
E. Type IV hypersensitivity
A
The correct answer is E.The tuberculin reaction is an example of delayed-type hypersensitivity (a
form of Type IV hypersensitivity) in which the bulk of the tissue damage is done by macrophages that
are stimulated by a few previously sensitized CD4+ memory T-cells recognizing antigens presented
by the macrophages. In contrast, in T-cell mediated cytotoxicity (choice C, another form of Type IV
sensitivity) the damage is done by CD8+ cytotoxic T-cells that recognize “foreign” cell surface
antigens and directly lyse targeted cells.
Antibody-dependent cell-mediated cytotoxicity reactions (choice A, a form of Type II hypersensitivity)
involves cells coated with a thin layer of antibody that triggers attack by cells (monocytes, neutrophils,
eosinophils, and natural killer cells) that can bind to Fc receptors.
Local anaphylaxis (choice B, a form of Type I hypersensitivity) is caused by the release of vasoactive
substances by mast cells and basophils stimulated by memory (CD4+) T-cells reacting to antigen.
Type III (choice D) hypersensitivity is caused by deposition of circulating antigen-antibody complexes,
often in small blood vessels.
16
Q
- Which of the following is characterized by extreme weakness, fatigue, nausea, stomach
cramps, hypotensive while sitting and even more on standing, hyperkalemia, increased
freckling around the eyes, and darkening of the palmar creases?
A. Addison’s disease
B. Conn’s syndrome
C. Cushing’s syndrome
D. Secondary adrenal insufficiency
E. Tertiary adrenal insufficiency
A
The correct answer is A. Addison’s disease usually occurs because of autoimmune destruction of
the adrenal cortex (all three zones are typically involved), resulting in decreased secretion of cortisol,
aldosterone, and adrenal androgens. Hyperpigmentation is the classic physical finding, resulting from
increased serum ACTH caused by loss of negative feedback inhibition by cortisol at the pituitary or
hypothalamus. The increase in pigmentation may occur because the first 13 amino acids of ACTH are
identical to alpha-melanocyte stimulating hormone. Low serum levels of cortisol produce
gastrointestinal symptoms such as nausea, vomiting, and anorexia. Fatigue and weakness are almost
always reported. Blood pressure is usually low and orthostatic hypotension may be present, because
arterioles are less responsive to the constrictor effects of catecholamines in the absence of cortisol.
The cardiovascular symptoms are worsened by the loss of blood volume caused by aldosterone
deficiency. Hyperkalemia is a manifestation of the low serum aldosterone; hyponatremia may also be
present.
Conn’s syndrome (choice B) results from hypersecretion of aldosterone. It is characterized by
hypertension, hypernatremia, and hypokalemia.
Cushing’s syndrome (choice C) occurs because of excessive secretion of cortisol. It is characterized
by central obesity, buffalo hump, moon facies, hypertension, and hypokalemia.
Secondary (choice D) and tertiary (choice E) adrenal insufficiency result in low serum levels of
ACTH. The subsequent hypocortisolism can produce the gastrointestinal complaints and fatigability
but not hyperkalemia. With deficiency of CRH or ACTH, serum aldosterone usually remains in the
normal range, and signs of mineralocorticoid deficiency are not present. Furthermore, low serum
levels of ACTH would not produce hyperpigmentation.
17
Q
- A 45-year-old man presents to a physician with back pain, facial pain, coarse facial
features, and kyphosis. His laboratory studies show elevated alkaline phosphatase. X-ray
studies demonstrate skull thickening with narrowing of foramina and bowing of the femur and
tibia. Bone biopsy reveals a mosaic pattern of bone spicules with prominent osteoid seams.
Which of the following neoplasms occurs at an increased frequency in patients with this
disorder?
A. Astrocytoma
B. Hodgkin lymphoma
C. Meningioma
D. Non-Hodgkin lymphoma
E. Osteosarcoma
A
The correct answer is E. The phrase “mosaic pattern” of newly formed woven bone is specific for
Paget disease of bone and is not seen in other bone conditions. The clinical and radiologic
presentation are typical; an increased hat size may also be a clue. In early stages, Paget disease is
characterized by osteolysis, producing patchwork areas of bone resorption with bizarre, large
osteoclasts. In the middle stage of the disease, secondary osteoblastic activity compensates with new
bone formation, producing the mosaic pattern. In late Paget disease, the bones are dense and
osteosclerotic. Paget disease is suspected to be related to prior viral infection, but the cause remains
unknown. Complications include myelophthisic anemia, high output cardiac failure, pain secondary to
8
nerve compression, deformities secondary to skeletal changes, and in approximately 1% of patients,
osteosarcoma or other sarcoma, typically involving the jaw, pelvis, or femur.
An increased incidence of astrocytomas (choice A) is associated with tuberous sclerosis.
Hodgkin lymphoma (choice B) is usually a disease of young adults, although older patients may have
the lymphocyte-depleted form.
Meningiomas (choice C) are mostly benign tumors that affect adults, especially women. There may
be an association with breast cancer, possibly related to high estrogen states.
Non-Hodgkin lymphoma (choice D) is more common in AIDS and other immunodeficiency states,
although the incidence in the immunocompetent is increasing.
18
Q
- Which of the following can be present with swollen and painful toes and knees, morning
low back stiffness, conjunctivitis, as well as mouth and skin ulcerations in a young adult?
A. Gout
B. Lyme disease
C. Reiter’s syndrome
D. Rheumatoid arthritis
E. Septic arthritis
A
The correct answer is C. This is a description of Reiter’s syndrome. Patients typically present with
the acute onset of arthritis (usually asymmetric and additive), with involvement of new joints occurring
over a period of a few days to 2 weeks. Joints of the lower extremities are the most commonly
involved, but wrists and fingers can also be affected. Dactylitis (sausage digit), a diffuse swelling of a
solitary finger or toe, is a distinctive feature of Reiter’s arthritis and psoriatic arthritis. Tendonitis and
fasciitis are common, as are spinal pain and low back pain. Oligoarthritis, conjunctivitis, urethritis, and
mouth ulcers are the most common features. The mucocutaneous lesions may include balanitis,
stomatitis, and keratoderma blennorrhagicum. Microorganisms that can trigger Reiter’s syndrome
include Shigella spp., Salmonella spp., Yersinia spp., Campylobacter jejuni, and Chlamydia
trachomatis. Most patients are younger males.
Gout (choice A) usually presents as an explosive attack of acute, very painful, monarticular
inflammatory arthritis. Hyperuricemia is the cardinal feature and prerequisite for gout. The first
metatarsophalangeal joint is involved in more than 50% of first attacks.
Lyme disease (choice B), caused by Borrelia burgdorferi, presents with a red macule or papule at the
site of the tick bite. This lesion slowly expands to form a large annular lesion with a red border and
central clearing. The lesion is warm, but usually not painful. The patient also has severe headache,
stiff neck, chills, arthralgias, and profound malaise and fatigue. Untreated infection is associated with
development of arthritis in the large joints (e.g., knees) lasting for weeks to months.
Rheumatoid arthritis (choice D) begins insidiously with fatigue, anorexia, generalized weakness, and
vague musculoskeletal symptoms leading up to the appearance of synovitis. Pain in the affected
joints, aggravated by movement, is the most common manifestation of established rheumatoid
arthritis. Generalized stiffness is frequent, especially in the morning, and is usually greatest after
periods of inactivity. Rheumatoid arthritis is more common in females. The metacarpophalangeal and
proximal interphalangeal joints of the hands are characteristically involved.
Septic arthritis (choice E) is caused by a variety of microorganisms, including Neisseria gonorrhoeae
and Staphylococcus aureus. Hematogenous spread is the most common route in all age groups.
Approximately 90% of patients present with involvement of a single joint, usually the knee. The usual
presentation is moderate to severe pain, effusion, muscle spasm, and decreased range of motion.
19
Q
- Which of the following antigens would autoantibodies be directed against when there is
symmetrical swelling of the proximal phalangeal joints and large subcutaneous nodules over
the extensor surfaces of both arms of a older woman?
A. Acetylcholine receptor
B. Double stranded DNA
C. Histones
D. IgG
E. Ribonucleoprotein
A
The correct answer is D. The disease described is rheumatoid arthritis, and the autoantibody is
rheumatoid factor, which is usually an IgM or IgG (or less commonly IgA) directed against the
constant region of autologous IgG.
Autoantibody directed against acetylcholine receptors (choice A) is a feature of myasthenia gravis.
Autoantibody directed against double stranded DNA (choice B) is a feature of systemic lupus
erythematosus.
Autoantibody directed against histones (choice C) is a feature of drug-induced lupus.
Autoantibody directed against ribonucleoprotein (choice E) is a feature of mixed connective tissue
disease.
20
Q
- What is the BEST explanation for rapid weight gain, buffalo hump formation, prominent
vertical purple abdominal striae, and the increase of fasting blood glucose, plasma levels of
ACTH and cortisol, and also the presence of osteoporosis, hypertension, poor wound healing,
and hypokalemia in an older male?
A. Addison’s disease
B. An ectopic ACTH-secreting tumor
C. Conn’s syndrome
D. Cushing’s disease
E. Primary hypercortisolism
A
The correct answer is D. This is a description of “Cushingoid” signs and symptoms caused by
hypercortisolism. Although the acute effect of cortisol is to produce lipolysis, patients with chronically
increased cortisol levels develop a characteristic central obesity and buffalo hump. The extremities
are often thinned. The mechanism for the redistribution of body fat is not known but may involve an
interaction between cortisol and insulin. The weight gain with hypercortisolism usually results from
increased appetite. Cortisol excess causes protein catabolism, which leads to poor wound healing,
decreased connective tissue, and fragile blood vessels. The combination of thin skin and fragile blood
vessels leads to abdominal stretch marks (striae) that are characteristically purple in color. Because of
increased gluconeogenesis and decreased peripheral insulin sensitivity, blood glucose may be
increased. Osteoporosis, hypertension, poor wound healing, and hyperkalemia are also commonly
seen. If the hypercortisolism is caused by a functional tumor in the adrenal cortex (primary
hypercortisolism, choice E), plasma concentration of ACTH should be low because of negative
feedback suppression. Increased cortisol and increased ACTH could result from a functional ACTHsecreting
tumor in the pituitary (Cushing’s disease) or an ectopic tumor (such as a small cell
carcinoma of the lung, choice B).
Addison’s disease (choice A) is primary adrenal insufficiency, and whereas plasma ACTH is
increased (producing hyperpigmentation), plasma cortisol and aldosterone are decreased (not
increased) compared with normal.
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Conn’s syndrome (choice C) results from hypersecretion of aldosterone by the adrenal cortex. Some
of the clinical manifestations overlap with Cushing’s disease: for example, both may exhibit
hypertension. In the case of Conn’s syndrome, this is caused by excessive renal sodium and water
reabsorption because of increased aldosterone levels. In Cushing’s disease, it is due in part to the
mineralocorticoid-like effects of high plasma cortisol.
21
Q
- What condition is marked by dilated cardiomyopathy, slow speech and intellectual
function, fatigue, lethargy, cold intolerance, listlessness, thickened facial features, periorbital
edema, dry, coarse skin, and peripheral edema, and also with low serum levels of T4 and high
ones of TSH?
A. Cretinism
B. Grave’s disease
C. Hyperthyroidism
D. Myxedema
E. Thyroid cancer
A
The correct answer is D. Myxedema is caused by long-standing hypothyroidism in adults.
Myxedema can result from the many causes of hypothyroidism: Hashimoto’s thyroiditis, idiopathic
primary hypothyroidism, iodine deficiency, drugs, pituitary lesions, hypothalamic lesions, and damage
to the thyroid by surgery or radiation.
Cretinism (choice A) is caused by hypothyroidism in infancy.
Grave’s disease (choice B) usually produces hyperthyroidism.
Hyperthyroidism (choice C) describes the signs and symptoms associated with an overproduction of
thyroid hormone. Because the body’s metabolism is increased,patients often feel hotter than those
around them and can slowly lose weight even though they may be eating more. The weight issue is
confusing sometimes since some patients actually gain weight because of an increase in their
appetite. There is usually fatigue at the end of the day, but have trouble sleeping. Trembling of the
hands and a hard or irregular heartbeat (called palpitations) may develop. These individuals may
become irritable and easily upset. When severe, there can be shortness of breath, chest pain, and
muscle weakness.
Thyroid cancer (choice E) often causes a painless swelling in the region of the thyroid. Thyroid
function tests are usually normal.
22
Q
- Which of the following occurs after an upper respiratory infection and involves severe
lower back pain, generalized muscle weakness, and distal paresthesia and demyelination, but
there is no appreciable sensory loss and there is minimal residual sequelae?
A. Creutzfeldt-Jakob disease
B. Friedreich ataxia
C. Huntington’s disease
D. Multiple sclerosis
A
The correct answer is D. This describes Guillain-Barr syndrome, also known as acute idiopathic
inflammatory polyneuropathy. This condition, which typically follows an upper respiratory or other
infection by several days to a month, is caused by an autoimmune attack on the myelin of peripheral
nerves. In this respect, it is most similar to multiple sclerosis, which is an autoimmune attack on the
myelin in the brain and spinal cord. Most cases of Guillain-Barr syndrome resolve spontaneously. A
few patients have recurrences, and rare patients die during the acute episode of respiratory muscle
failure (artificial ventilation may be required).
Creutzfeldt-Jakob disease (choice A) is an Alzheimer-like condition caused by a prion (protein
infectious agent).
11
Friedreich ataxia (choice B) is an autosomal recessive disorder associated with spinocerebellar
degeneration. Ataxia and paralysis are seen beginning in adolescence.
Huntington’s disease (choice C) is an autosomal dominant degeneration of the caudate and frontal
lobes characterized by movement disorder and dementia.
23
Q
- Which of the following can involve lassitude, myalgia, mylar rash, joint pain, elevated
urinary protein, with the blood showing leukopenia and a high titer of antinuclear antibodies?
A. Generalized fatigue
B. Goodpasture’s syndrome
C. Systemic lupus erythematosus
D. Scleroderma
A
The correct answer is C. Systemic lupus erythematosus (SLE) is a prototype connective tissue
disease. The diagnosis requires four criteria to be met from a list of 11 possible criteria: malar rash,
discoid rash, photosensitivity, oral ulcers, arthritis, serositis, renal disorder, neurologic disorder,
hematologic disorder, immunologic disorder, and antinuclear antibody. The appearance of a malar or
“butterfly” rash seen in approximately half of all patients is generally the easiest way to diagnose this
condition on the dental boards. Antinuclear antibodies (ANA) are present in 95-100% of cases of SLE;
anti-double-stranded DNA is found in 70% of the cases.
Generalized fatigue (choice A) can occur in anyone, but the presence of the other criteria make SLE
more likely.
Goodpasture’s syndrome (choice B) is characterized by linear disposition of immunoglobulin and
often C3 along the glomerular basement membrane (GBM). Glomerulonephritis, pulmonary
hemorrhage, and occasionally idiopathic pulmonary hemosiderosis occur.
Scleroderma (choice D) is characterized by thickening of the skin caused by swelling and thickening
of fibrous tissue, with eventual atrophy of the epidermis. ANA are often associated with the disease,
but the staining pattern is generally nucleolar.
24
Q
- Which of the following cancers may develop when there are islands of red tissue noted
above the gastroesophageal junction in situations involving chronic reflux of gastric contents
into the esophagus?
A. Adenocarcinoma of the esophagus
B. Adenocarcinoma of the stomach
C. Sarcoma of the esophagus
D. Sarcoma of the stomach
E. Squamous cell carcinoma of the esophagus
A
The correct answer is A. The lesion is Barrett’s esophagus, which is related to chronic reflux of
gastric contents into the esophagus. This lesion predisposes for the development of adenocarcinoma
of the distal esophagus, which is the most serious complication of Barrett’s esophagus. The
development of adenocarcinoma of the esophagus is approximately 40 times higher in patients with
Barrett’s esophagus compared with those without the lesion.
Conditions predisposing for adenocarcinoma of the stomach (choice B) include chronic atrophic
gastritis, pernicious anemia, and postsurgical gastric remnants.
Sarcoma of the esophagus (choice C) or stomach (choice D) is rare.
Plummer-Vinson syndrome predisposes for squamous cell carcinoma of the esophagus (choice E).
25
24. Which of the following when removed from the diet will help improve a history of weight
loss, diarrhea, flatulence, greasy stools, and increased fecal fat and marked atrophy of villi?
A. Beef
B. Eggs
C. Potatoes
D. Tomatoes
E. Wheat
The correct answer is E. This describes celiac sprue which is caused by an allergic, immunologic, or
toxic reaction to the gliadin component of gluten from wheat, as well as rye, barley, and oats, but not
rice or corn. The symptoms and pathologic changes usually reverse with complete removal of gliadin
from the diet. Therapeutic failures are frequently caused by hidden wheat in the diet. Patients with
celiac disease have an increased risk for developing gastrointestinal lymphoma. The classic signs and
symptoms of celiac sprue include weight loss, flatuence, greasy stools, and increased fecal fat. A
diagnosis can be confirmed when clinical improvement is made on a gluten-free diet.
26
25. Which of the following is the MOST likely explanation for a rash in a leukemic patient that
consists of multiple erythematous patches on the arms, legs, palms, and soles, some of which
show central clearing and surrounding ring formation?
A. Urticaria
B. Erythema multiforme
C. Kaposi's sarcoma
D. Psoriasis
The correct answer is B. The presence of erythematous patches with central clearing, known
clinically as target lesions, is associated with erythema multiforme. Both erythema multiforme and its
severe, life-threatening version, known as Stevens-Johnson syndrome, are produced by immune
complex deposition in dermal blood vessels. In approximately 50% of patients, no specific
precipitating cause is identified. In the remainder of patients, however, a variety of causes have been
implicated, including certain infections (herpes simplex, enteroviruses, Mycoplasma pneumoniae,
Chlamydia, histoplasmosis), drugs, neoplasia, sarcoidosis, and foods. Some penicillins and
corticosteroids can also cause this condition.
Urticaria (choice A) causes wheals that are intensely pruritic, but does not produce target lesions.
Kaposi's sarcoma (choice C) causes purple lesions with no target lesions.
Psoriasis (choice D) causes erythematous plaques with silvery scales but does not produce target
lesions.
27
26. A 72-year-old man with a significant smoking history presents with dyspnea, facial
erythema, and facial, truncal, and arm edema with prominence of thoracic and neck veins.
Chest x-ray reveals a mass in the right mediastinum with adenopathy. Which of the following
is the most likely diagnosis?
A. Adenocarcinoma
B. Hodgkin lymphoma
C. Large cell carcinoma
D. Non-small cell carcinoma
E. Small cell carcinoma
The correct answer is E. Superior vena cava (SVC) syndrome is characterized by obstruction of
venous return from the head, neck, and upper extremities. More than 85% of cases of SVC syndrome
are related to malignancy. Bronchogenic carcinomas (most commonly small cell cancer and
13
squamous cell cancer) account for more than 80% of these cases. Among bronchogenic carcinomas,
the most common causes of SVC syndrome (in order of frequency) are small cell carcinoma,
epidermoid carcinoma, adenocarcinoma (choice A), and large cell carcinoma (choice C).
Lymphomas such as Hodgkin disease (choice B) and non-Hodgkin lymphoma are uncommon causes
of SVC syndrome. Rare tumors associated with SVC syndrome include primary leiomyosarcomas and
plasmacytomas. Infectious etiologies include tuberculosis, syphilis, and histoplasmosis. SVC
syndrome can also occur as a result of an enlarged goiter, and from thrombus formation caused by
indwelling intravenous lines or pacemaker wires.
Non-small cell carcinoma (choice D) is not commonly associated with SVC syndrome.
28
```
27. What can be present when there is digital clubbing and tenderness over the distal ends of
the radius, ulna, and fibula?
A. Gastrointestinal cancer
B. Liver cancer
C. Lung cancer
D. Renal cancer
E. Testicular cancer
```
The correct answer is C. This patient has the finger clubbing and hypertrophic pulmonary
osteoarthropathy that can be associated with bronchogenic carcinoma (other than squamous cell
carcinoma), benign mesothelioma, and diaphragmatic neurilemmoma. X-ray of the bones generally
shows formation of new periosteal bone; arthritis may be present. The etiology of these changes
remains a mystery. An alert clinician may identify a cancer at an earlier, potentially curable stage by
investigating a possible paraneoplastic syndrome. Digital clubbing is caused by chronically low
oxygen levels. This condition affects the fingers and toes in which proliferation of the distal tissues,
especially the nail beds, results in broadening of the extremities of these digits. The affected nails are
abnormally curved and shiny.
29
28. Which of the following lesions are present in an adult with newly diagnosed tuberculosis?
A. A single lesion in a lung apex
B. A single lesion in the gastrointestinal tract
C. A single lesion subjacent to the pleura
D. A lesion subjacent to the pleura in the lower part of an upper lobe and active disease in the
mediastinal lymph nodes
E. Multiple tiny masses throughout the body
The correct answer is A. Because tuberculosis is transmitted primarily by "droplet" transmission by
way of the nasopharynx, it is essential that the dental student understand the basic principles of
tuberculosis. Primary tuberculosis infection characteristically involves the lung subjacent to the pleura
in either the lower part of the upper lobe or the upper part of a lower lobe of one lung. The mediastinal
nodes are also usually involved (choice D), rather than having a single lesion subjacent to the pleura
(choice C) without lymph node involvement. Roughly 80% of newly diagnosed pulmonary
tuberculosis cases in adults are actually caused by reactivation of an often clinically unsuspected
infection acquired years to decades previously. The reinfection site usually is in the apex of the lung.
The source of reinfection is usually a Gohn complex, or calcified granuloma of giant cells,
mycobacteria leukocytes, and fibrous cells.
The lungs are not the only site where tuberculosis can occur (it can occur throughout the body), and
isolated gastrointestinal involvement (choice B) is (uncommonly) also seen.
Miliary tuberculosis (rare) is a widely disseminated and dangerous form of tuberculosis characterized
by small lesions throughout the body (choice E). It is more common in immunocompromised patients.
30
29. Which of the following is involved when there is excessive bleeding after labor, and the
laboratory studies demonstrate decreased platelets, prolonged prothrombin time and partial
thromboplastin time, and increased fibrin split products?
A. Disseminated intravascular coagulation
B. Hemophilia A
C. Severe liver disease
D. Vitamin K deficiency
E. Von Willebrand's disease
The correct answer is A. Thsi is a description of disseminated intravascular coagulation (DIC), a
feared and often life-threatening complication of many other disorders, including amniotic fluid
embolism, infections (particularly gram-negative sepsis), malignancy, and major trauma. This is
suspected when a decrease in platelets and a prolongation of PT and PTT times are observed. The
observed hematologic abnormalities are caused by consumption of platelets and clotting factors,
caused by extensive microclot formation with accompanying fibrinolysis (reflected by the increased
fibrin split products).
Hemophilia (choice B) alters the PTT without affecting the other indices.
Severe liver disease (choice C) produces alterations comparable to those in vitamin K deficiency;
platelets can also be decreased secondary to a generalized metabolic marrow dysfunction, but fibrin
split products would not be increased.
Vitamin K deficiency (choice D) is associated with alterations in PT and PTT, but platelets will not be
decreased, nor will fibrin split products be increased.
Von Willebrand's disease (choice E) produces impaired platelet adhesion and increases the bleeding
time and the PTT, but will not produce the other features described.
31
30. Which of the following can account for a child developing fever, conjunctivitis,
photophobia, cough, white spots on a bright red background on the buccal mucosa, and a
rash that begins around the hairline, then spreads to the trunk and extremities?
A. Aphthous ulcers
B. Herpetic stomatitis
C. Laryngeal papillomas
D. Measles
E. Oral thrush
The correct answer is D. This description is of measles, with the appearance of Koplik's spots (white
spots on the buccal mucosa) followed by a rash beginning along the neck and hairline and spreading
to the trunk and extremities. The sequela of this condition may be postinfectious encephalomyelitis
that can follow infection with measles, varicella, rubella, mumps, influenza, or vaccination with
vaccinia vaccine or rabies vaccine derived from nervous tissue.
Aphthous ulcers (choice A) are easy to recognize because they are round ulcerations with yellowgray
fibrinoid centers surrounded by red halos.
Herpetic stomatitis (choice B) is common, mild, short-lived, and requires no intervention. There is an
initial burning followed by small vessicles that rupture to form scabs.
Laryngeal papillomas (choice C) are common lesions of the larynx and other sites where ciliated and
squamous epithelia meet. Hoarseness progresses to stridor over the course of weeks to months.
Oral thrush (choice E) is associated with the development of painful, creamy white, curd- like patches
overlying erythematous mucosa.
32
31. What is present when an elderly person can no longer recognize people and common
objects, plan activities, and wanders with an absent look on their face, but who is still happy,
yet frustrated by the memory loss, and speech is limited to simple two- or three-word
sentences?
A. Alzheimer's disease
B. Amnestic disorder
C. Clinical depression
D. Substance-induced persisting dementia
E. Parkinson's disease
The correct answer is A. This is a description of dementia of the Alzheimer's type. A gradual onset
of symptoms, general pervasive memory deficit, difficulties with language, and inability to plan,
leading to severe impairment of daily functioning are all characteristic of dementia of the Alzheimer's
type.
Amnestic disorder (choice B) is limited to memory problems; and not cognitive dysfunction, such as
alterations in language and the loss of the ability to plan.
Clinical depression (choice C) is associated with feelings of helplessness and hopelessness.
Cognitive function is not impaired.
The diagnosis of substance-induced persisting dementia (choice D) requires evidence of a history of
substance abuse. It is the second most likely diagnosis, however, and should be carefully explored.
Parkinson's disease (choice E) is associated with develpment of dyskinesia, postural instability,
moonlike facies, and difficulty performing daily activities.
33
32. Which of the following substances would be MOST likely be elevated due to the
development of large osteoblastic bone lesions in a patient with prostate cancer?
A. Prostatic acid phosphatase
B. Prostate specific antigen
C. Serum alkaline phosphatase
D. Serum uric acid
E. Leukocytes
The correct answer is C. Osteoblastic cells respond to metastatic prostate carcinoma by forming
bone (osteoid), and secreting alkaline phosphatase, which is believed to initiate or facilitate
mineralization.
Prostatic acid phosphatase (choice A) and prostatic-specific antigen (choice B) are synthesized by
the tumor and would most likely be elevated; however, they are elevated because of the prostatic
cancer independent of the bony metastasis. Serum uric acid (choice D) would be expected to be
seen in patients with gout. White blood cells (choice E) can be elevated by a bacterial infection,
rheumatoid arthritis, and several medications, including glucocorticoids and lithium. In other words,
elevated white blood cells is often a nonspecific indicator.
34
33. Which of the following pair of hormones regulates the hormone responsible for a middleaged
man experiencing gradual coarsening of facial features, progressive protrusion of the
lower jaw, and having to wear larger shoes and gloves?
A. Dopamine and norepinephrine
B. LH and hCG
C. Prolactin and FSH
D. Somatostatin and GHRH
E. TSH and ACTH
The correct answer is D. The disease described is acromegaly, which is typically produced by a
growth hormone-secreting pituitary adenoma. Growth hormone synthesis is predominantly regulated
by hypothalamic GHRH (growth hormone-releasing hormone), and its pulsatile secretion is
predominantly regulated by hypothalamic somatostatin. Clinical features of acromegaly include
excessive growth of hands and feet in adults, protusion of the lower jaw, coarsening of facial features,
and a deeper voice.
Dopamine and norepinephrine (choice A) are catecholamines that regulate smooth muscle tone and
cardiac function.
Choice B is incorrect because luteinizing hormone (LH) regulates sex steroid hormone production by
testes and ovaries; human chorionic gonadotropin (hCG) is produced by the placenta and has actions
similar to LH.
Choice C is incorrect because prolactin regulates menstruation and lactation, whereas follicle
stimulating hormone (FSH) regulates ovarian and testicular function.
Choice E is incorrect because thyroid stimulating hormone (TSH) regulates secretion of thyroid
hormones and adrenocorticotropin (ACTH) regulates glucocorticoid secretion.
35
34. Which of the following tissues or organs may be associated with hyperplasia and
neoplastic proliferation if there is fatigue, feeling of constant coldness, diffusely enlarged and
rubbery thyroid gland, while laboratory tests show low T3 and T4, high TSH, large numbers of
lymphocytes of all degrees of maturation, a few abnormal follicular cells with eosinophilic
granular cytoplasm, and only rare normal follicular cells?
A. Colon
B. Esophagus
C. Peripheral nerve
D. Skin
E. Thymus
The correct answer is E. The thyroid disease is Hashimoto's thyroiditis, an autoimmune disease in
which the thyroid parenchyma is destroyed by a lymphocytic infiltrate. The infiltrate typically contains
mature follicles; the remaining scanty follicular cells often have eosinophilic granular cytoplasm and
are called Hurthle cells or oncocytes. Clinically, patients usually have hypothyroidism, although brief
periods of hyperthyroidism ("Hashitoxicosis") may also be seen. Like myasthenia gravis, Hashimoto's
disease may be associated with thymic disorders, including thymic hyperplasia, benign thymomas,
and malignant thymomas.
Colon (choice A) cancer is associated with ulcerative colitis and adenomatous polyps.
The risk for esophageal cancer (choice B) is increased with Barrett's esophagus and in Plummer-
Vinson syndrome.
You should associate neurofibromas of peripheral nerve (choice C) with cafe au lait spots on the skin.
Skin cancer (choice D) occurs with greater frequency in association with xeroderma pigmentosa and
actinic keratosis.
36
35. What is occuring when an esophagus is dilated, kinked, tortuous, partly filled with
undigested foods, and is associated with chronic dysphagia?
A. Achalasia
B. Barrett's esophagus
C. Hiatal hernia
D. Plummer-Vinson syndrome
E. Zenker's diverticulum
The correct answer is A. Achalasia (from the Greek "unrelaxed") is a disease of ganglion cells in the
esophageal myenteric plexus causing a failure of relaxation in the lower esophageal (cardiac)
sphincter. The cause of achalasia is usually not determined. The peristaltic waves in the esophagus
stop before the sphincter, and the food collects in the esophagus, which becomes dilated and
elongated.
Barrett's esophagus (choice B) is metaplastic replacement of the squamous esophageal epithelium
with columnar epithelium. Barrett's esophagus is an important risk factor for esophageal
adenocarcinoma.
Hiatal hernia (choice C) is a protrusion of the stomach into the thorax by way of the diaphragmatic
hiatus, at the lower esophageal sphincter. Although hiatal hernia can produce gastroesophageal
reflux, the esophagus does not become distended and food passes normally into the stomach.
Plummer-Vinson syndrome (choice D) is a constellation of physical findings associated with severe
iron-deficiency anemia including koilonychia, atrophic glossitis, and dysphagia caused by atrophy of
the pharyngeal mucosa and mucosal webs in the upper esophagus.
Zenker's diverticulum (choice E) is an oropharyngeal diverticulum occurring at the junction of the
pharynx and esophagus which occurs because of wall weakness in the esophagus at this location,
and may produce dysphagia.
37
36. What is involved in a smoker with scant clear mucoid sputum, quiet sounding chest,
hemoptysis, weight loss, detruction of alveolar septae around the respiratory bronchioles,
with marked enlargement of the airspaces, and heavy deposits of anthracotic pigment?
A. Asthma
B. Chronic bronchitis
C. Emphysema
D. Pulmonary hypertension
E. Silicosis
The correct answer is C. Emphysema is a pulmonary disease characterized by enlargement of the
alveolar airspaces caused by destruction of the septae without consequent fibrosis. The gross
appearance of emphysematous lungs is characteristic: alveoli are sufficiently dilated to allow
visualization with the naked eye and destruction of structural support to lymphatic vessels produces
heavy pigment deposition in the tissue. Microscopic findings that confirm the diagnosis include
enlarged, round airspaces with club-like ends of broken septae sticking into the alveoli. There is scant
clear mucoid sputum. The chest is very quiet without adventitious sounds.
Asthma (choice A) is a disease of airway hyperreactivity and is characterized by hypertrophy of the
bronchial basement membranes and smooth muscle, with glandular hyperplasia and thick mucus
plugs in the bronchi. Wheezing will be heard on expiration.
Chronic bronchitis (choice B) produces marked hypersecretion of mucopurulent mucus in the large
airways and can be identified by hypertrophy of mucous glands in the bronchi and goblet cell
hyperplasia in the smaller airways. The chest is noisy with rhonci invariably present. Wheezing is
common.
Pulmonary hypertension (choice D) affects neither the airways nor the alveoli. It is characterized by
thickening of the arterial smooth muscle with intimal hyperplasia and fibrosis. Atherosclerotic changes
in the normally plaque-free larger pulmonary arteries may be seen.
Silicosis (choice E), one of the forms of pneumoconiosis, is an interstitial fibrosing disease that
produces thick pleural scars and dense nodules of collagen that may calcify. The silica particles may
be visualized within the nodules using polarized light.
38
```
37. What presents with painful widespread erosions on the mucous membranes with friability,
no well-defined borders, acantholysis, and with direct immunofluorescence demonstrate an
intraepidermal band of IgG and C3?
A. Bullous pemphigoid
B. Dermatitis herpetiformis
C. Herpes simplex I
D. Herpes simplex II
E. Pemphigus vulgaris
```
The correct answer is E. This is a description of pemphigus vulgaris, in which autoantibody directed
against transmembrane cadherin adhesion molecules induces acantholysis (breakdown of epithelial
cell-cell connections) with resulting intraepidermal blister formation. It has an insidious onset of flaccid
bullae in crops or waves. It may develop spontaneously or following triggers such as drugs (thiols,
penicillamine), physical injury (burns), cancer, pregnancy, other skin diseases, and emotional stress.
Pemphigus vulgaris is a relatively rare blistering disease; it is seen more commonly in patients with
Jewish or Mediterranean heritage. The epidermis at the edge of these erosions is often easily
disrupted by sliding pressure (Nikolsky sign). Pemphigus vulgaris begins in the mouth in 50% of
cases. Acantholysis is seen on biopsy.
Bullous pemphigoid (choice A) is characterized by deeper blisters occurring at the dermal-epidermal
junction.
Dermatitis herpetiformis (choice B) is characterized by severe, intense pruritus and groups of papules
and vesicles.
Herpes simplex I (choice C) or II (choice D) can show multinucleated giant cells on scrapings of the
ulcer base.
39
38. Which of the following thyroid diseases is most likely related to restlessness, fever,
profuse sweating, marked tachycardia and tremor during labor, later developing delirium,
nausea, vomiting, and abdominal pain between contractions?
A. Follicular carcinoma
B. Grave's disease
C. Hashimoto's thyroiditis
D. Hypertensive urgency
E. Papillary carcinom
The correct answer is B. This is a description of a thyrotoxic crisis that occurs most commonly in
untreated or inadequately treated Grave's disease. The onset is typically abrupt and may be
precipitated by stressors that can include infection, trauma, radioiodine treatment, and childbirth. The
condition, if unrecognized, may progress to congestive cardiac failure, pulmonary edema, and death.
Both follicular (choice A) and papillary (choice E) carcinomas of the thyroid gland are usually
nonsecretory and consequently do not produce hyperthyroidism.
Hashimoto's thyroiditis (choice C) is an autoimmune thyroiditis that may transiently produce
hyperthyroidism before producing hypothyroidism, but thyrotoxic crisis is not usually a feature.
Hypertensive urgency (choice D) is a situation in which blood pressure must be reduced in a few
hours. Most patients are asymptomatic with severe hypertension (systolic > 220 mmHg or diastolic >
125 mmHg)
40
39. Which of the following is the most probable etiology for a young person with acute
bacterial endocarditis limited to the tricuspid valve?
A. Congenital heart disease
B. Illicit drug use
C. Rheumatic fever
D. Rheumatoid arthritis
E. Rheumatic heart disease
The correct answer is B. The most probable etiology of bacterial endocarditis involving the tricuspid
valve is illicit intravenous drug use, which can introduce skin organisms into the venous system that
then attack the tricuspid valve. Staphylococcus aureus accounts for 60-90% of cases of endocarditis
in intravenous drug users. This is an important concept for dentists because some patients with drug
seeking behaviors, such as the intravenous drug abuser, may present to a dental office in search of
narcotic medications.
The endocarditis associated with congenital heart disease (choice A) typically involves either
damaged valves or atrial or ventricular septal defects. The tricuspid valve is not particularly
vulnerable.
Rheumatic fever (choice C) most commonly damages the mitral and aortic valves, and tricuspid
damage is usually less severe and seen only when the mitral and aortic valves are heavily involved.
Consequently, secondary bacterial endocarditis involving only the tricuspid valve in a patient with a
history of rheumatic fever would be unusual.
Rheumatoid arthritis (choice D) is not associated with bacterial endocarditis, unless there is an
association with SLE.
Rheumatic heart disease (choice E) which occurs after rheumatic fever and again involves mainly the
mitral and aortic valves.
41
40. What is the specific mechanism by which death is produced from breathing carbon
monoxide in a closed space?
A. Damage to the plasmalemma
B. Decreased oxygen-carrying capacity of blood
C. Increased calcium transport into mitochondria
D. Poisoning of oxidative phosphorylation
E. Rupture of lysosomes
The correct answer is B. Carbon monoxide has a very high affinity for hemoglobin, and binds, nearly
irreversibly, in such a manner that oxygen cannot bind, drastically decreasing the oxygen-carrying
capacity of the blood. Carbon monoxide also causes the oxygen-hemoglobin dissociation curve to
shift to the left, making oxygen more difficult to unload. Traditionally, carbon monoxide poisoning have
been described as having "cherry red" blood and skin, but this change is somewhat unreliable in real
life.
Choices A, C, and E list secondary changes that are commonly observed in injured cells, no matter
what the cause of the injury.
Cyanide acts by poisoning oxidative phosphorylation (choice D).
42
```
41. Which of the following clinical features would be most likely to be present when thyroid
function tests reveal increased TSH, decreased total T4, decreased free T4, and decreased T3
uptake?
A. Diarrhea
B. Heat intolerance
C. Hyperactivity
D. Palpitations
E. Weight gain
```
The correct answer is E. The laboratory studies are typical for primary hypothyroidism, in which the
thyroid fails to produce adequate T4 despite appropriate TSH signals from the pituitary gland. Clinical
features of hypothyroidism include weight gain, cold intolerance, hypoactivity, fatigue, lethargy,
decreased appetite, constipation, weakness, decreased reflexes, facial and periorbital myxedema, dry
and cool skin, and brittle hair.
In contrast, diarrhea (choice A), heat intolerance (choice B), hyperactivity (choice C), and
palpitations (choice D) are features of hyperthyroidism.
43
```
42. Which of the following findings would be MOST consistent for a young person in a coma
having an acetone-like odor?
A. Alcohol intoxication
B. Diabetic hyperosmolar coma
C. Diabetic ketoacidosis
D. Heroin overdose
E. Profound hypoglycemia
```
The correct answer is C. The smell of acetone on the breath of a comatose person is an important,
rapid diagnostic clue that strongly suggests ketoacidosis and is usually seen in patients with poorly
controlled type 1 diabetes mellitus. Other features of diabetic ketoacidosis include high blood glucose,
increased serum osmolality, hypovolemia, acidosis, and electrolyte imbalance. It is important to note
that diabetic ketoacidotic coma is usually preceded by a day or more of polyuria and polydipsia
associated with marked fatigue, confusion, and nausea.
In alcohol intoxication (choice A), the breath will smell like alcohol. Some may confuse a patient with
diabetes in ketoacidosis as being "drunk," however, because of the similar smell.
Diabetic hyperosmolar coma (choice B) usually is seen in older patients with type 2 diabetes mellitus
and is not characterized by ketoacidosis. Because there is no acetone production, there is no specific
scent to the breath. In heroin overdose (choice D), no acetone production occurs and there is no
specific scent to the breath. In hypoglycemic coma (choice E), which can occur in diabetics with
insulin overdose, no acetone production occurs and there is no specific scent to the breath.
44
43. A 24-year-old man presents with complaints of itching on his arms and face. He states that
he took four 500-mg capsules of amoxicillin 1 hour before a dental procedure. Physical
examination reveals well circumscribed wheals with raised, erythematous borders and
blanched centers. Which form of hypersensitivity is this patient probably exhibiting?
A. Acute serum sickness (Type III)
B. Antibody-dependent cell-mediated cytotoxicity (Type II)
C. Antireceptor antibodies (Type II)
D. Delayed type hypersensitivity (Type IV)
E. Immediate type hypersensitivity (Type I)
The correct answer is E. Urticaria (hives) is a good example of a local anaphylaxis reaction that is
classified as a Type I hypersensitivity reaction. Type I hypersensitivity reactions involve preformed IgE
antibody bound to mast cells or basophils that release vasoactive and spasmogenic substances when
they react with antigens. Certain allergens, especially drugs, insect venoms, latex, and foods may
induce an IgE antibody response, causing a generalized release of mediators from mast cells leading
to a systemic reaction.
Acute serum sickness (choice A) is now uncommon but was formerly seen when animal sera were
used for passive immunization. Serum-like sickness has also been seen in patients receiving
cephalosporins, such as cefaclor.
The eosinophil-mediated cytotoxicity against parasites is an example of antibody-dependent cellmediated
cytotoxicity (choice B).
Myasthenia gravis is an example of a disease caused by antireceptor antibodies (choice C).
The tuberculin (PPD) reaction used to test for tuberculosis exposure is an example of delayed-type
hypersensitivity (choice D).
45
44. Which of the following notations in a chart indicates the greatest likelihood that a 1-cm,
flat,white patch on the buccal mucosa will progress to a malignancy?
A. Hairy leukoplakia
B. Leukoplakia
C. Linea alba
D. Oral thrush
E. Squamous papilloma
The correct answer is B. Leukoplakia is a white plaque on the oral mucosa for which a more specific
diagnosis cannot be rendered. For example, unlike oral candidiasis the white lesion cannot be
removed by rubbing the oral mucosal surface. Leukoplakia is often associated with hyperkeratosis
and may or may not show dysplastic squamous epithelium. On average, 2-6% represent either
dysplasia or early invasive squamous cell carcinoma.
Hairy leukoplakia (choice A) is an oral infective lesion seen almost exclusively in patients with HIV
infection. It is a fluffy, white, hyperkeratotic lesion in which a destructive piling up of keratotic squames
is seen. Hairy leukoplakia is associated with viral infection, mostly EBV, HPV, or HIV. It does not
progress to cancer.
Linea alba (choice C) is a linear white area on the buccal mucosa formed from hyperkeratosis due to
occlusion, and may be excessive in those that clench or grind.
Oral thrush (choice D) is a superficial candidal infection, typically occurring in immunosuppressed or
very young patients. Thrush is an infectious, non-neoplastic disease.
Squamous papilloma (choice E) is a benign human papillomavirus (HPV) infection of the oral
mucosa. Typically associated with HPV genotypes 6 and 11, squamous papilloma only rarely
progresses to squamous carcinoma.
46
45. Which of the following is present in a elderly person that has thin arms and legs, a swollen
abdomen, red tongue, dry, thin, and slightly yellow skin, gynecomastia, testicular atrophy,
multiple spider angiomas, tremor, yellow discoloration of sclera, and short-term memory loss?
A. Bronchogenic carcinoma
B. Colon carcinoma
C. Congestive heart failure
D. Type 2 diabetes mellitus
E. Hepatic cirrhosis
The correct answer is E. The physical examination is typical for an alcoholic with advanced hepatic
cirrhosis. It is important to recognize these symptoms, as these patients are notorious for
"underestimating" and even denying their alcohol use.
Bronchogenic carcinoma (choice A) typically presents with cough or respiratory changes, but can
present with mass effects in the chest or involvement of mediastinal nerves or vessels.
Colon cancer (choice B) typically presents with changes in the stool or bowel habits.
Congestive heart failure (choice C) is typically heralded by shortness of breath or peripheral edema,
or both.
Type 2 diabetic patients (choice D) are typically obese and present with usual signs and symptoms of
diabetes, such as polyuria, polydipsia, and polyphagia (but not ketoacidosis).
47
46. Which of the following laboratory tests is performed following a head injury so as to
differentiate between nephrogenic and neurogenic diabetes insipidus?
A. Creatinine in a 24-hour urine collection
B. Urine osmolality after vasopressin administration
C. Serum renin after infusion of hypotonic saline
D. Serum sodium after infusion of hypertonic saline
The correct answer is B. Diabetes insipidus is characterized by the excretion of abnormally large
volumes of dilute urine (polyuria) with a commensurate increase in fluid intake (polydipsia). There are
two types, neurogenic and nephrogenic. The most common type is neurogenic diabetes insipidus,
which is caused by inadequate secretion of antidiuretic hormone (ADH) or vasopressin. In the
absence of ADH, a brisk diuresis results; the osmolality of the urine may be extremely low. Many with
neurogenic (central) diabetes insipidus have a history of head trauma, brain tumors, or brain
infections that damage the hypothalamus or neurohypophysis. Nephrogenic diabetes insipidus, which
presents in much the same way, can be seen in association with certain renal diseases caused by a
defect in the renal V2 vasopressin receptor, Gs protein, or other steps in the formation of cyclic AMP.
Plasma levels of vasopressin are usually increased, because of the hyperosmolarity of the serum.
Water deprivation will fail to increase urine osmolarity in neurogenic and nephrogenic diabetes
insipidus. Because V2 receptors are functional in neurogenic diabetes insipidus, however,
administration of exogenous ADH will still concentrate the urine, whereas this would be ineffective in
nephrogenic diabetes insipidus.
Measurement of creatinine (choice A) in a 24-hour urine collection, coupled with plasma creatinine
values and the urine flow rate can be used to approximate glomerular filtration rate.
Renin secretion would be inhibited by infusion of hypotonic saline (choice C) in neurogenic and
nephrogenic diabetes.
Serum sodium (choice D) would rise with infusion of hypertonic saline in either type of diabetes
insipidus.
48
47. Which of the following laboratory results would be expected in a child with 2 standard
deviations below the expected mean height, delayed bone maturation, goiter, and a point
mutation in the thyroid hormone receptor?
A. Decreased radioactive iodine uptake test
B. Increased plasma T4 concentration
C. Decreased plasma TSH concentration
D. Increased basal metabolic rate
The correct answer is B. Generalized resistance to thyroid hormone is a rare genetic abnormality
(Refetoff syndrome). It results from mutations of the thyroid hormone receptor gene. Depending on
the severity of the disorder, patients may be only mildly affected or may exhibit striking hypothyroid-
23
like symptoms including decreased basal metabolic rate (BMR) (not increased, choice D). Growth
can be stunted, there may be deaf mutism, and attention span may be short. Because the thyroid
hormone resistance is generalized, the normal negative feedback effects of T4 and T3 at the
hypothalamus and pituitary are also deficient. This would lead to an increased plasma TSH
concentration (not decreased, choice C). Because of the increase in plasma TSH, iodine trapping by
the thyroid follicular cells will be increased, leading to an increase in radioactive iodine uptake test
(RAIU) (not decreased, choice A) and an increase in serum T4.
49
48. What form of arthritis is present in an elderly woman that complains of ill-fitting dentures,
dry eyes and mouth, and severe arthritic pain?
A. Gonococcal arthritis
B. Gouty arthritis
C. Osteoarthritis
D. Pseudogout
E. Rheumatoid arthritis
```
The correct answer is E. Dry eyes and mouth in an elderly woman are probably caused by Sjogren's
syndrome, an autoimmune attack on the salivary and tear glands. Sjogren's syndrome is associated,
in some cases, with rheumatoid arthritis.
Gonococcal arthritis (choice A) is a systemic complication of gonorrhea, typically observed in young
women who have had a recent sexual encounter.
Gout (choice B) and pseudogout (choice D) can cause arthritis secondary to crystal deposition in
joints.
Osteoarthritis (choice C) seems to be caused by repetitive low-level trauma to joints
```
50
49. A 7-year-old boy is not having any behavioral problems in school, but he is having a great
deal of trouble paying attention in class. He has normal IQ and cognitive function, but
occasionally asks that questions be repeated after staring blankly into space for a few
seconds. Which of the following disorders most likely accounts for these symptoms?
A. Absence seizures
B. Attention deficit hyperactivity disorder
C. Schizophrenia with childhood onset
D. Parkinson disease
The correct answer is A. The patient described in this question is suffering from absence seizures
that typically appear during childhood between the ages of 5 and 7 years. In absence seizures, the
patient has many episodes of brief disruption of consciousness throughout the day. These seizures
are not accompanied by the convulsions and complete loss of consciousness often associated with
epilepsy, but rather by the absence of motor or sensory symptoms (hence the blank look on the
patient's face).
Children with attention deficit hyperactivity disorder (choice B) also have a limited attention span and
normal intelligence. They also exhibit hyperactivity, impulsiveness, emotional lability, and irritability,
however, which lead to behavioral problems in school.
Schizophrenia with childhood onset (choice C) is rare. Children with this disorder demonstrate normal
intelligence and may show a limited attention span. These children also manifest the same psychiatric
symptoms seen in adult-onset schizophrenics, however, including hallucinations, delusions, abnormal
affect, and limited social skills that lead to behavioral problems in school.
Parkinson disease (choice D) most commonly onsets between ages 45-65 years. It is associated with
any combination of tremor, rigidity, bradykinesia, and progressive postural instability
51
```
50. Which of the following hormones is most likely secreted by mass in the head of the
pancreas in a person with multiple intractable gastric and duodenal peptic ulcers and marked
elevation of gastric acid secretion?
A. Calcitonin
B. Epinephrine
C. Gastrin
D. Parathormone
E. Vasoactive intestinal peptide
```
The correct answer is C.This is a description of Zollinger-Ellison syndrome in which a duodenal or
pancreatic gastrin-secreting endocrine tumor causes hypersecretion of gastric acid. Two thirds of
these tumors are malignant. One third are related to MEN I that also causes parathyroid
hyperplasia/adenomas and pituitary adenomas.
Calcitonin (choice A) is usually secreted by medullary carcinoma of the thyroid.
Epinephrine (choice B) is secreted in pheochromocytoma.
Pancreatic endocrine tumors may also secrete vasoactive intestinal peptide (VIP, choice E),
parathyroid hormone (choice D), parathyroid hormone-related peptide, insulin, glucagon,
somatostatin, ACTH, or growth hormone-releasing hormone (GHRH). Secretion of these hormones is
less common than secretion of gastrin and is not specifically suggested by the peptic ulcer history.
52
51. Which of the following findings would MOST likely also be present with a history of
scleroderma that has a near absence of smooth muscle peristalsis and lower esophageal
sphincter tone?
A. Anemia
B. Atrophic glossitis
C. Hourglass-shaped stomach on barium swallow
D. Massively dilated colon
E. Muscle replaced with connective tissue
The correct answer is E. Near complete absence of muscle tone and peristalsis is characteristic of
involvement of the esophagus with scleroderma, which causes replacement of muscle by dense
connective tissue. Similar changes in the dermis cause the skin to be thickened. The thickened, shiny
skin of the hands may cause them to resemble claws with telangiectasia and areas of increased
pigmentation and depigmentation. Systemic features include dysphagia and hypomotility of the
gastrointestinal tract.
Anemia (choice A) and atrophic glossitis (choice B) are associated with esophageal webs in
Plummer-Vinson syndrome.
An hourglass-shaped stomach within the thoracic cavity (choice C) is a feature of a sliding hiatal
hernia. A massively dilated esophagus (megaesophagus) can be caused by Chagas' disease, a
trypanosomal disease that can also cause massive dilation of the colon (choice D).
53
```
52. Which of the following is the MOST significant risk factor for breast cancer in a 40-year-old
woman?
A. Breast-feeding after pregnancy
B. Caffeine consumption
C. Cigarette smoking
D. Family history
E. Nulliparity
```
The correct answer is D. Positive family history is definitively the most significant risk factor for
developing breast cancer among the ones mentioned. Approximately 5-10% of cases are attributable
to inheritance of autosomal dominant genes. Most hereditary cases of breast cancer are caused by
two genes, BRCA1 and BRCA2, which are tumor suppressor genes probably involved in DNA repair.
Note, however, that 80-90% of women with breast cancer do not have a positive family history.
Breast-feeding after pregnancy (choice A) is not considered a risk factor for breast cancer. Although
research is ongoing, it may be that the breast cancer risk in women who breast-feed is decreased.
There is no convincing evidence linking caffeine consumption or cigarette smoking (choices B and C)
to breast cancer.
Breast cancer is more frequent in nulliparous women than in multiparous women. Nulliparity (choice
E) is therefore a risk factor, but its role is considered less important than family history. Similar to a
long duration of reproductive life and late age at first intercourse, nulliparity (never given birth to a
child) seems to increase breast cancer risk by increasing exposure to endogenous estrogen during
the menstrual cycle.
54
53. A child with cystic fibrosis may have a history of meconium ileus, chronic cough, frequent
respiratory tract infections, and bulky, foul-smelling stools and _______ ?
A. Cystinuria
B. Hypoglycemia
C. Iron deficiency anemia
D. Laryngeal papillomas
E. Pancreatic insufficiency
The correct answer is E. This is a descriptionof cystic fibrosis. In this disorder, an abnormality of
chloride channels causes all exocrine secretions to be more viscous than normal. Because of
pancreatic insufficiency, the pancreatic secretion of digestive enzymes is often severely impaired, with
consequent steatorrhea and deficiency of fat-soluble vitamins, including vitamin A.
Cystinuria (choice A) is a common disorder in which a defective transporter for dibasic amino acids
(cystine, ornithine, lysine, arginine) leads to saturation of the urine with cystine, which is not very
soluble in urine, and precipitates out to form stones.
Hypoglycemia (choice B) is not a prominent feature of children with cystic fibrosis who are on a
normal diet. Hyperglycemia may occur late in the course of the disease.
Iron deficiency anemia (choice C) is not found with any regularity in children with cystic fibrosis.
Laryngeal papillomas (choice D) are common lesions of the larynx. Unlike in the oral cavity, when
found in the larynx they are likely to be symptomatic, with hoarseness that progresses to stridor over
weeks to months.
55
```
54. What are multiple long-standing tan to brownish lesions on the face and back of older
individuals that are slightly raised with a rough surface,typically 0.5-1.5 cm in diameter, and
that show an ability to be peeled off?
A. Eczema
B. Melanoma
C. Psoriasis
D. Seborrheic keratoses
E. Verruca vulgaris
```
The correct answer is D.Chronic eczema (choice A) produces dry, thick, and sometimes discolored
skin.
26
Melanomas (choice B) characteristically look like dark moles with irregular margins and variations in
the degree of pigmentation.
Psoriasis (choice C) produces erythematous plaques with a silvery scale.
Verruca vulgaris (choice E), the common wart, produces verrucous papules that are most commonly
found on the hands. The face and back would be unusual sites.
56
55. Which of the following laboratory findings would be MOST likely in a teenage girl with
delayed puberty, short stature, webbed neck, low-set ears, fish-like mouth, and ptosis?
A. Decreased plasma growth hormone
B. Decreased plasma growth hormone
C. Increased plasma follicle stimulating hormone
D. Increased plasma inhibin
E. Increased plasma estrogen
The correct answer is C. This is a description of Turner's syndrome which is a result of a 45, XO
karyotype and which is characterized by ovarian dysgenesis and a variety of somatic abnormalities
including micrognathia, a fish-like mouth, a shield chest, low-set ears, ptosis, and a webbed neck.
Other findings can include coarctation of the aorta, hypertension, and renal abnormalities. Short
stature is invariably present; the cause is not known because plasma levels of growth hormone
(choice A) and thyroid hormone (choice B) are typically not decreased. Clinical studies have shown,
however, that injections of human growth hormone can increase the final height. The ovaries are
usually streak-like and exhibit only fibrous stroma which leads to decreased secretion of estrogen (not
increased, choice E) and inhibin (not increased, choice D) and persistent infantilism. Plasma levels
of FSH are markedly increased because of the lack of feedback inhibition by ovarian secretions.
57
56. Which of the following presents with a painful, swollen knee, geographic tongue, and
resolving psoriasiform rash on the palms and soles, as well as urethritis and conjunctivitis?
A. Gout
B. Bacillary arthritis
C. Osteoarthritis
D. Osteoporosis
E. Rheumatoid arthritis
The correct answer is E. This is an example of Reiter's syndrome (urethritis, cervicitis in females,
conjunctivitis, arthritis, and mucocutaneous lesions). The term keratoderma blennorrhagicum is used
for the lesions of the palms and soles that resemble pustular psoriasis. Geographic tongue is caused
by erosions histologically characterized by prominent spongiform pustules. Lesions of the glans penis
(balanitis circinata) may also be present. Reiter's syndrome is associated with chlamydial infection in
70% (or more) of cases. The arthritis that can be seen in the disease is an inflammatory arthritis
similar to that of rheumatoid arthritis.
Gout (choice A) is a crystal arthritis; other examples of crystal arthritis include apatite-associated
arthritis and pseudogout caused by calcium pyrophosphate dihydrate crystals.
If you believed the patient has gonococcal arthritis (a septic arthritis), then gram-negative bacillary
arthritis (choice B) would be a good choice. Neisseria gonorrhoeae is not noted for causing
conjunctivitis, however, which should have steered you toward Reiter's syndrome.
Osteoarthritis (choice C) is a degenerative disorder without systemic manifestations. X-ray findings
typically show narrowed joint space, osteophytes, and an increased density of subchondral bone.
Osteoporosis (choice D) can be asymptomatic to severe backache from vertebral fractures.
Demineralization of the spine, hip, and pelvis is common.
58
```
57. Which of the following can be noted in a rheumatoid arthritic that has acute caries and
chronic parotid gland enlargement?
A. Oral squamous cell carcinoma
B. Polyarteritis nodosa
C. Sjogren's syndrome
D. Systemic lupus erythematosus
E. Thyrotoxicosis
```
The correct answer is C. Rheumatoid arthritis can coexist with a variety of autoimmune diseases
(including those listed in the answers), but is most frequently associated with Sjogren's syndrome.
Sjogren's syndrome classically presents with keratoconjunctivitis (dry eyes) and xerostomia (dry
mouth, often resulting in dental caries and fissures in the oral mucosa). These symptoms are caused
by autoimmune involvement with subsequent scarring of the salivary and lacrimal glands. Parotid
gland enlargement is common and may be chronic or relapsing and develops in approximately one
third of patients with Sjogren's syndrome. Vasculitis, Raynaud's phenomenon, hyperviscosity
syndrome, and peripheral neuropathy may also be seen.
The development of oral squamous cell carcinoma (choice A) is not related to the presence of dental
caries.
Polyarteritis nodosa (choice B) is a systemic necrotizing vasculitis. There is typically present with lowgrade
fever, weakness, and weight loss. Abdominal pain, hematuria, renal failure, hypertension, and
leukocytosis may occur.
Systemic lupus erythematosus (choice D) is an autoimmune disease characterized by vasculitis,
rash, renal disease, hemolytic anemia, and neurologic disturbances.
Thyrotoxicosis (choice E) is not related to the development of dental caries.
59
58. Which of the following is the cause of joint pain involving the large leg joints in a young
adult accompanied by diarrhea that is often bloody?
A. Amebic colitis
B. Chronic appendicitis
C. Diverticulosis
D. Pseudomembranous colitis
E. Ulcerative colitis
The correct answer is E. Several gastrointestinal diseases are associated with rheumatologic
complaints. The most frequent of these are the chronic inflammatory bowel diseases, ulcerative
colitis, and Crohn's disease, which can be associated with sacroiliitis or lower limb arthritis. Other
gastrointestinal diseases associated with arthropathy include bypass surgery, Whipple's disease,
Behcet's syndrome, and celiac disease. Ulcerative colitis is accompanied by bloody diarrhea, lower
abdominal cramps and fecal urgency, anemia, low serum albumin, and negative stool culture.
Sigmoidoscopy is the key to diagnosis.
Amebic colitis (choice A) is caused by ingestion of infectious cysts (typically from Entamoeba
histolytica). Symptoms include abdominal pain and diarrhea; malaise and weight loss may occur.
Cecal amebiasis can resemble acute appendicitis.
Chronic appendicitis (choice B) may be asymptomatic or cause poorly defined abdominal pain.
Diverticulosis (choice C) is usually a disease of older adults. It is often asymptomatic unless
inflammation supervenes.
Pseudomembranous colitis (choice D) is a severe form of diarrhea usually seen in the setting of prior
antibiotic use. The causative organism is almost always Clostridium difficile.
60
59. Two diabetic patients are seen by a clinician. The first patient Comparing an older person
just diagnosed with diabetes that was identified by the presence of hyperglycemia and
diabetes in a young person who had previously presented with polyuria and polydipsia, the
younger person is more likely to:
A. be obese
B. become euglycemic with oral hypoglycemic agents
C. develop ketoacidosis
D. have relatively high endogenous insulin levels
E. have tissue insulin insensitivity
The correct answer is C. The younger person would have type 1 (used to be called juvenile onset)
diabetes mellitus, whereas the older person probably has type 2 (used to be called maturity onset)
diabetes mellitus. These two types of diabetes differ in many respects. Ketoacidosis is more apt to
develop in type 1, although it can occur in patients with type 2 after several years. As type 2
progresses, the amount of insulin secretion decreases more like type 1; therefore, the incidence of
ketoacidosis increases.
Type 2 tend to be obese (choice A), whereas type 1 are often thin.
Type 1 is usually apparently caused by viral or immune destruction of beta cells, whereas type 2 is
apparently usually caused by increased resistance to insulin; consequently the older diabetic rather
than the younger diabetic is more likely to have relatively high endogenous levels of insulin (choice
B).
Type 2 can often be controlled with oral hypoglycemic agents (choice D), whereas IDDM generally
require insulin. Note that some NIDDM also may require insulin as the disease evolves.
Tissue insulin insensitivity (choice E) or insulin resistance are the primary etiologic factors causing
NIDDM.
61
60. Which of the following processes is related to a asymptomatic perimenopausal woman
demonstrating bony swellings in the distal interpharyngeal joints; however no inflammation is
apparent and the proximal interphalangeal joints, hands, and wrists are not involved?
A. Autoantibody formation
B. Bacterial infection
C. Crystal deposition
D. Joint trauma
E. Viral infection
The correct answer is D. The disease is osteoarthritis and the bony swellings are called Heberden's
nodes, which may or may not be symptomatic. Osteoarthritis is believed to be related to repetitive
joint trauma. Osteoarthritis is a degenerative disorder with systemic manifestations. Pain is relieved by
rest. Radiographic findings include narrowed joint space, osteophyte, increased density of
subchondral bone, and bony cysts.
Autoantibodies (choice A) are important in rheumatoid arthritis.
Bacterial infections (choice B) cause septic arthritis.
Crystal deposition (choice C) is important in gout and pseudogout.
Viral infections (choice E) can cause transient arthralgias and arthritis.
62
61. Which of the following is present with a complaint of tiredness and muscle weakness, as
well as increased blood pressure, plasma sodium and plasma aldosterone, and decreased
plasma potassium, hematocrit, and plasma renin activity?
A. Addison's disease
B. Conn's syndrome
C. Cushing's syndrome
D. Hypothyroidism
E. Pheochromocytoma
The correct answer is B. Conn's syndrome is hyperaldosteronism caused by a hypersecreting
adrenal adenoma. Conn's syndrome is one of several endocrine causes of hypertension. The
hypertension is caused by volume expansion secondary to increased renal sodium and water
retention. The excessive aldosterone also causes increased renal excretion of potassium leading to
hypokalemia, which can explain the tiredness and muscle weakness. The decreased hematocrit is
also consistent with blood volume expansion. The increase in blood volume, blood pressure, and
plasma sodium all contribute to the suppression of renin secretion.
Addison's disease (choice A) is primary adrenal insufficiency and is characterized by decreased
secretion of cortisol and aldosterone. It is accompanied by hyponatremia and hyperkalemia.
Patients with Cushing's syndrome (choice C) can also be hypertensive. This may be, in part, to an
increased permissive action of cortisol on catecholamine-mediated vascular tone. In addition, cortisol
in high levels can have significant mineralocorticoid activity and can produce sodium retention and
potassium loss. The hypertension, sodium retention, and hypervolemia tend to suppress renin
secretion and may decrease aldosterone secretion. Cushing's syndrome is also characterized by a
redistribution of body fat, producing central obesity and a buffalo hump with the extremities being
thinned.
Hypothyroidism (choice D) is associated with weakness, fatigue, cold intolerance, constipation,
weight changes, and hoarseness. Dry skin, bradycardia, and a delayed return of deep tendon reflexes
are also present. This condition is caused by low T4 levels. TSH levels are generally elevated in
patients with primary hypothyroidism.
Pheochromocytoma (choice E) is another endocrine cause of hypertension. It is caused by a
catecholamine-secreting tumor. The hypertension is caused by excessive vasoconstriction and
increased cardiac output.
63
```
62. Which of the following additional findings would MOST likely be present in a child with
freckles all over his body, including the buccal mucosa, lips, palms, soles, and skin not
exposed to sun?
A. Colonic polyps
B. Desmoid tumors
C. Epidermoid cysts
D. Osteomas of the jaw
E. Pigmented ocular fundus
```
The correct answer is A. The widespread freckles (spots of melanin pigmentation) described are
associated with hamartomatous colonic polyps in the autosomal dominant condition Peutz-Jeghers
syndrome. The polyps in Peutz-Jeghers syndrome do not progress to colon cancer. Peutz-Jeghers
syndrome is associated with an increased potential to develop carcinomas of the pancreas, breast,
ovary, uterus, and lung. The hamartomas can become large enough to cause obstruction, bleeding, or
intussusception.
All of the other features listed are components of Gardner's syndrome, a variant of familial
adenomatous polyposis syndrome that carries a greatly increased risk for colon cancer.
64
```
63. In a PPD skin test that shows >10 mm of induration, which of the following type of reactive
cells would be found?
A. B lymphocyte
B. Eosinophil
C. Mast cell
D. Neutrophil
E. T lymphocyte
```
The correct answer is E. The CD4+ population of T lymphocytes, specifically TH1 cells, are
responsible for the delayed hypersensitivity reaction seen with a skin test in a previously sensitized
patient. This response to a PPD test is typically seen in reactivation or adult-type tuberculosis. A 10-
mm reaction on a skin test is considered positive if the person is in a high-incidence group (foreignborn,
medically underserved, low-income population, or resident of a long-term care facility).
B lymphocytes (choice A) are involved in humoral immune reactions. Antibody production is not a
feature of tuberculosis hypersensitivity.
Eosinophils (choice B) are important in type I hypersensitivity reactions and in immune-mediated
responses to parasitic infections (ADCC). They are not associated with tuberculosis hypersensitivity.
Mast cells (choice C) are tissue cells that are involved in type I hypersensitivity reactions. They have
surface receptors for the Fc fragment of the IgE molecule.
Neutrophils (choice D) are associated with acute inflammatory reactions. They are considered a
"nonspecific" cell in that they do not interact with an antigen. The neutrophil is not a classic cell type
seen in tuberculosis hypersensitivity.
65
```
64. Which of the following is the MAJOR chemotactic factor responsible for attracting
neutrophils?
A. C3b
B. C5a
C. IgM
D. IL-2
E. Lysozyme
```
The correct answer is B. In active inflammation, the complement system has been activated and
C5a is being produced, which is a strong chemoattractant to neutrophils and other phagocytic cells.
C3b (choice A) is an excellent opsonin of pathogenic organisms; when an organism is coated with
C3b, it is more easily phagocytized. C3b is formed by way of the classic and alternative complement
pathways.
IgM (choice C) is the first immunoglobulin produced in the primary immune response. IgM cannot
cross the placenta, but it is a powerful activator of complement; elevated levels in the newborn are
associated with an acute infection with a pathogen.
IL-2 (choice D) is a powerful interleukin that stimulates T helper 1 cells. It also stimulates natural killer
cells and T cytotoxic CD8 lymphocytes, but is not chemotactic for neutrophils.
Lysozyme (choice E) is a material present in tears, mucus, vaginal secretions, and other body fluids.
It is active against the peptidoglycan of bacterial cell walls, splitting the backbone structure of the
peptidoglycan (N-acetylglucosamine and N-acetyl muramic acid polymers).
66
```
65. Which of the following is characterized by a young boy with failure to thrive, recurrent
seizures, hepatomegaly, renomegaly, severe hypoglycemia, hyperlipidemia, lactic acidosis,
and ketosis?
A. Gaucher's disease
B. McArdle's disease
C. Niemann-Pick disease
D. Pompe's disease
E. von Gierke's disease
```
The correct answer is E. von Gierke's disease is a glycogen storage disease caused by a deficiency
of glucose-6-phosphatase. It typically presents with neonatal hypoglycemia, hyperlipidemia, lactic
acidosis, and ketosis. Failure to thrive is common in early life; convulsions may occur because of
profound hypoglycemia. The glycogen accumulation in von Gierke's disease occurs primarily in the
liver and kidneys, accounting for the enlargement of these organs. Gout may develop later because of
the derangement of glucose metabolism.
Even if you do not remember all of the details of the presentation of these genetic diseases, you
should be able to narrow the choices:
Gaucher's disease (choice A) and Niemann-Pick disease (choice C) are lipid storage diseases and
would not be expected to produce hypoglycemia.
The other diseases are glycogen storage diseases, but McArdle's disease (choice B) and Pompe's
(choice D) disease affect muscle rather than liver and would not be expected to produce profound
hypoglycemia, because the liver is the major source for blood glucose.
67
66. Which of the following disorders is associated with the same oncogenic virus that is the
likely cause of nonkeratinizing squamous cell carcinoma of the nose, pharynx, and sinuses?
A. Adult T-cell leukemia
B. Burkitt's lymphoma
C. Cervical carcinoma
D. Hepatocellular carcinoma
E. Kaposi's sarcoma
The correct answer is B. The cancer described is nasopharyngeal carcinoma, which is associated
with Epstein Barr virus (EBV). This virus is also associated with the African form of Burkitt's lymphoma
that characteristically involves the jaw.
HTLV-1, or human T-lymphocyte virus, is associated with adult T-cell leukemia (choice A).
HPV, or human papillomavirus, is associated with cervical carcinoma (choice C), penile carcinoma,
and anal carcinoma. Hepatitis B virus (HBV) is associated with hepatocellular carcinoma (choice D).
HHV 8, a member of the herpes family, is associated with Kaposi's sarcoma (choice E).
68
67. What is at risk to develop when there is substernal burning pain exacerbated by large
meals, cigarettes, and caffeine, and laying on the back, especially when sleeping at night, but
improved with antacids?
A. Cardiac ischemia
B. Columnar metaplasia of the distal esophagus
C. Mallory-Weiss lesion in the esophagus
D. Squamous cell carcinoma
E. Zenker's diverticulum
The correct answer is B. This is a description of reflux esophagitis, a condition in which the lower
esophageal sphincter (LES) does not adequately prevent acidic gastric contents from refluxing back
into the distal esophagus. Most commonly, there is a defect in the LES mechanism itself, in addition to
secondary causes such as pregnancy (from increased abdominal pressure) and some medications.
Symptoms can mimic cardiac chest pain and must be carefully evaluated for complications including
esophageal strictures, ulcerations, laryngitis, pulmonary aspiration, and Barrett's esophagus
(columnar metaplasia of the distal esophagus). Barrett's esophagus is considered a premalignant
state, with roughly a 40-fold increase in the incidence of esophageal adenocarcinoma. The normal
squamous epithelium of the esophagus transforms into columnar epithelium similar to gastric
epithelium as a result of recurrent reflux of acidic gastric contents.
Anginal pain, signaling cardiac ischemia (choice A), is generally not burning in nature and is not
relieved by antacids.
Mallory-Weiss lesions (choice C) are actual tears of the epithelia of the proximal stomach or distal
esophagus as a result of retching, nausea, and vomiting (seen in patients with anorexia and
alcoholism).
The incidence of pure squamous cell carcinoma (choice D) is not increased by acid reflux disease.
Zenker's diverticula (choice E), the most common of esophageal diverticuli, are not true diverticuli,
but only mucosal herniations that can cause obstructive symptomatology.
69
68. Which of the following in a middle-aged person can cause a persistent, long term
productive cough with a past history of smoking and with the recent presence of a green
sputum and fever?
A. Bronchogenic carcinoma
B. Chronic bronchitis with superimposed infection
C. Cystic fibrosis
D. Emphysema
E. Pulmonary tuberculosis
The correct answer is B. Chronic bronchitis requires the presence of chronic productive cough over
at least 3 months of the year for 2 successive years. The green productive sputum and fever suggest
that there is an acute infection superimposed on chronic bronchitis (history of cigarette smoking,
history of excessive mucus production over many years). Histologically, the mucus-producing glands
in the bronchi would show hyperplasia and hypertrophy and extend to a greater depth in the bronchial
wall, resulting in a higher Reid index (ratio of thickness of mucus gland to thickness of bronchial wall).
Although smoking is involved and there is an increased risk for bronchogenic carcinoma (choice A),
this is unlikely. Hemoptysis and weight loss would also be present if cancer was involved. Cystic
fibrosis (choice C) presents earlier in life and may be associated with severe production of mucus,
especially if bronchiectasis supervenes. Age and the relative late onset of disease preclude this.
Emphysema may be involved (choice D), as chronic bronchitis and emphysema are often coexistent.
Although pure emphysema might cause dyspnea, it would not, however, be associated with a fever or
a productive cough. Pulmonary tuberculosis (choice E) would typically present with hemoptysis rather
than abundant green sputum. Weight loss, night anorexia, malaise, and weakness may also be
present.
70
69. What is noted histologically with extensive pruritic wheals following ingestion of certain
seafoods?
A. Dilated superficial lymphatic channels
B. Granular complement and IgG at the dermal/epidermal junction
C. Microscopic blisters
D. Munro microabscesses
E. Solar elastosis
```
The correct answer is A. Urticaria (hives) are pruritic wheals that form after mast cells degranulate
and trigger localized dermal edema with dilated superficial lymphatic channels with an allergic
response (commonly to certain types of shellfish). The mast cell degranulation is sometimes but not
always triggered by IgE-antigen interactions.
Granular complement and IgG deposition at the dermal/epidermal junction (choice B) is a
characteristic of systemic lupus erythematosus.
Microscopic blisters (choice C) are a characteristic of dermatitis herpetiformis.
Munro abscesses (choice D) are a characteristic of psoriasis.
Solar elastosis (choice E) is found in actinic keratoses.
```
71
70. Which will increase in the plasma and can cause an acid-base disorder in an uncontrolled
type 1 diabetic having breath that smells like nail polish remover?
A. Formic acid
B. Glycolic acid
C. Ketoacids
D. Lactic acid
E. Oxalic acid
The correct answer is C. Ketoacidosis can easily occur in patients with type 1 diabetes mellitus
secondary to the body's inability to produce insulin. This is metabolic acidosis (low pH, low HCO3-).
The decrease in arterial CO2 is a compensatory response to the acidosis. The smell of acetone
(which is the primary solvent of nail polish) on the breath of a diabetic suggests ketoacidosis and
uncontrolled type 1 diabetes mellitus. Because acetone is highly volatile, it is excreted mainly by the
lungs. Other common causes of ketoacidosis include starvation and the acute drinking-vomiting binge
of the alcoholic.
Plasma levels of formic acid (choice A) increase when methanol is ingested.
Plasma levels of glycolic acid (choice B) and oxalic acid (choice E) increase when ethylene glycol is
ingested.
Because lactic acid (choice D) is a product of anaerobic metabolism, its rate of production is
increased by decreases in tissue blood flow and oxygen delivery and when oxygen use is impaired.
Lactic acidosis commonly occurs in circulatory failure. Although diabetes mellitus can cause lactic
acidosis, it is far less common than ketoacidosis.
72
71. A 25-year-old man experiences the gradual onset of intermittent diarrhea that over years
progresses to severe diarrhea, alternating with constipation, rectal bleeding, and passage of
mucus. On examination, the abdomen is tender over the colon, and stool examination fails to
reveal parasites. Colonoscopy demonstrates inflammation limited to the rectum, with no
higher lesions. Which of the following diseases is most consistent with this history?
A. Celiac disease
B. Pseudomembranous colitis
C. Traveler's diarrhea
D. Ulcerative colitis
E. Whipple disease
The correct answer is B. The presentation is classic for Crohn disease and ulcerative colitis. Family
members of those afflicted show increased incidence of ulcerative colitis and Crohn disease, evidence
that these two diseases are actually different ends of the same spectrum. In contrast to Crohn disease
in which the lesions may be patchy and involve the distal ileum and even the esophagus, ulcerative
colitis lesions involve the rectum and may extend continuously proximally for varying distances up to
the cecum and very distal end of the ileum.
34
Celiac disease (choice A) is a small intestinal disease related to gluten intolerance. Flattening of villi,
elongated crypts, and marked inflammation in the lamina propria are noted histologically.
Pseudomembranous colitis (choice B), or antibiotic induced colitis, is commonly seen following
antibiotic therapy, especially with clindamicin. This condition is treated with metronidazole or
vancomycin and is caused by the toxin produced by Clostridium difficile.
Traveler's diarrhea (choice C) is generally seen in patients traveling from one country to another. It
has an acute onset and is generally associated with severe diarrhea.
Whipple disease (choice E) is an intestinal diarrheal disease that has been shown to be caused by a
bacterial infection.
73
```
72. What disease state can be present when focal calcification is found above the sella turcica,
and there is visual field abnormalities and diabetes insipidus, while needle biopsy shows
tissue resembling tooth enamel?
A. Craniopharyngioma
B. Glioblastoma multiforme
C. Large pituitary adenoma
D. Medulloblastoma
E. Pituitary microadenoma
```
The correct answer is A. The tumor described is a craniopharyngioma, alternatively known as an
adamantinoma or ameloblastoma. Craniopharyngiomas may arise in, or more commonly above, the
sella turcica. The histologic pattern recapitulates the enamel organ of the tooth, with nests or cords of
stratified squamous or columnar epithelium embedded in a loose fibrous stroma. Calcification (and
even metaplastic bone formation) is common in these benign tumors that are believed to arise from
vestigial remnants of Rathke's pouch.
Glioblastoma multiforme (choice B) characteristically shows at least some enlarged cells with bizarre
nuclei.
Large pituitary adenomas (choice C) contain nests of uniform glandular cells.
Medulloblastoma (choice D) is made of small basophilic cells with relatively large nuclei for their size.
Pituitary microadenomas (choice E) contain nests of uniform glandular cells.
74
```
73. Which of the following locations listed is the more common primary site for oral squamous
cell carcinoma?
A. Ventral tongue surface
B. Buccal mucosa
C. Floor of mouth
D. Palate
E. Tip of tongue
```
The correct answer is C. Oral cancers are highly associated with alcohol and tobacco use,
excessive sun exposure, and HPV-16 (human papilloma virus type 16, which is also found in cervical
carcinomas) is found in nearly half of all oral cancers. The pattern of tumor development possibly
reflects exposure-related or tissue classification factors. In decreasing order of frequency in regards to
risk of oral cancer, the following can be stated: (1) floor of the mouth (choice C); (2) tip of the tongue
(choice E); (3) hard palate (choice D); (4) ventral tongue surface (choice A); and (5) buccal mucosa
(choice B).
It is important to note that a systematic intraoral examination, including the entire oral cavity and lips,
with particular emphasis on the lateral tongue, floor of the mouth, and soft palate complex, as well as
palpation of the neck for enlarged hard lymph nodes should be part of any general head and neck
35
examination. This is especially true for patients over the age of 45 years who smoke tobacco or drink
alcohol excessively or are exposed to excessive amounts of sun.
75
74. Which of the following conditions explains the pain in the upper portion of the neck on
swallowing, with regurgitation of undigested food shortly after eating?
A. Mallory-Weiss tears
B. Plummer-Vinson syndrome
C. Schatzki rings
D. Traction diverticula
E. Zenker's diverticulum
The correct answer is E. This is a description of Zenker's diverticulum, which is a false diverticulum
formed by herniation of the mucosa at a point of weakness at the junction of the pharynx and
esophagus in the posterior hypopharyngeal wall. The cause is believed to be loss of elasticity of the
upper esophageal sphincter. Zenker's diverticulum is also associated with halitosis, and if the
diverticulum fills completely with food, it can cause dysphagia or obstruction of the esophagus.
Mallory-Weiss tears (choice A) are mucosal tears at the gastroesophageal junction secondary to
repeated, forceful vomiting. They are often seen in alcoholics and result in the appearance of blood in
the emesis.
Plummer-Vinson syndrome (choice B) is the triad of dysphagia (caused by esophageal webs in the
upper esophagus), atrophic glossitis, and iron-deficiency anemia.
Schatzki rings (choice C) are mucosal rings found in the distal esophagus at the squamocolumnar
junction.
In contrast to a Zenker's diverticulum, the usually asymptomatic traction diverticula (choice D) are
true diverticula involving all of the layers of the esophagus. They are typically caused by adherence of
the esophagus to a scarred mediastinal structure.
76
```
75. Which of the following findings would suggest pemphigus vulgaris as opposed to bullous
pemphigoid?
A. Eosinophils within bullae
B. Negative Nikolsky's sign
C. IgG autoantibody activity
D. Oral mucosal lesions
```
The correct answer is D. Pemphigus vulgaris is associated with chronic, severe bullae formation on
the skin and oral mucosa. Mucosal lesions are extremely rare in bullous pemphigoid. This can be
used clinically to guide therapy, although a skin biopsy should be taken to confirm the diagnosis. Both
diseases are characterized by formation of tender bullae that can rupture, leaving red, raw areas.
Pemphigus vulgaris patients eventually become febrile and lose weight, and if untreated, most will die
within 1 year. Bullous pemphigoid lesions tend to heal and the patients do very well. This prognostic
difference is an important distinction in dermatologic medicine.
Eosinophils within blisters (choice A) provide an important clue supporting bullous pemphigoid as the
diagnosis that must be ascertained with histologic examination. The vesicles in pemphigus vulgaris
mostly contain rounded acantholytic keratinocytes "floating" within.
Nikolsky's sign consists of separation of the epidermis on manual stroking of the skin. Bullous
pemphigoid is characterized by a negative Nikolsky's sign (choice B), but Nikolsky's sign is positive in
pemphigus vulgaris because of the IgG-mediated destruction of intercellular bridges between
keratinocytes.
IgG autoantibody activity (choice C) is common to pemphigus vulgaris and bullous pemphigoid.
36
77
76. A 30-year smoker walks into clinic, breathing heavily and complaining of dyspnea and
constant fatigue. On physical examination, the physician observes a "barrel chest" (expanded,
with increased anteroposterior diameter) and hypertrophy of the accessory respiratory
muscles. No cyanosis is evident. Occasionally he develops episodes of nonproductive cough,
but he denies asthma attacks. Blood gas analysis shows minimal hypoxemia and normal CO2.
Which of the following underlying pathogenetic mechanisms is most likely responsible for this
patient's condition?
A. Airway obstruction
B. Bronchospasm
C. Chest wall deformity
D. Interstitial infiltration
E. Loss of elastic recoil
The correct answer is E. This patient is the classic pink puffer with chronic obstructive pulmonary
disease (COPD). COPD is an umbrella term that refers to overlapping clinical conditions resulting
from a combination of emphysema, asthma, bronchiectasis, and chronic bronchitis. If emphysema is
predominant, patients with COPD have severe dyspnea (puffers), scanty sputum production, and
nearly normal O2 arterial pressure, and thus no cyanosis (pink). Loss of elastic recoil is characteristic
of emphysema, which is caused by destruction of alveolar walls and enlargement of airspaces distal
to terminal bronchioles. Cigarette smoking is clearly the most important cause of COPD. Destruction
of the pulmonary elastic fibers brings about increased resistance to airflow. The lungs become
overexpanded; although total pulmonary capacity increases, the functioning lung parenchyma
decreases. In emphysema the major complaint is dyspnea, often severe. Cough is rare with scant
clear mucoid sputum. No peripheral edema is noted.
Airway obstruction (choice A) is prevalent in patients who have COPD with predominant chronic
bronchitis (i.e., blue bloaters. Decreased PaO2 manifests with cyanosis (blue), and bronchitis causes
abundant sputum production. Pulmonary hypertension and right ventricular overload produce
peripheral edema (bloaters). The patient in this case does not fit this description.
Bronchospasm (choice B) is associated with asthma, a frequent component of COPD. Attacks of
asthma are caused by spasm of bronchiolar smooth muscles, resulting in increased resistance to
expiration. The clinical history clearly rules out bronchospasm as the fundamental mechanism of this
patient's condition.
Chest wall deformity (choice C), such as severe kyphoscoliosis and obesity, and interstitial infiltration
(choice D), usually caused by interstitial fibrosis, are responsible for restrictive pulmonary disease.
Restrictive pulmonary disease leads to decreased lung compliance and reduction in all respiratory
volumes. The barrel-chest deformity of this patient is a consequence, not a cause, of the underlying
pathologic change (i.e., overexpansion of the lungs).
78
77. What is the MOST likely cause for profuse upper gastrointestinal bleeding with
hematemesis and unconsciousness in an alcholic?
A. Barrett's esophagus
B. Helicobacter gastritis
C. Mallory-Weiss tear
D. Schatzki ring
E. Zenker's diverticulum
The correct answer is C. This is a description of a Mallory-Weiss tear, which is a mucosal tear at the
gastroesophageal junction secondary to recurrent vomiting (the stomach temporarily evulses through
the esophagus, tearing the esophagus). The result can be massive hematemesis, but the lesions
usually heal without problems if the patient does not die from exsanguination. Mallory-Weiss tears
account for 5-10% of cases of upper gastrointestinal bleeding. Most patients report history of heavy
alcohol abuse.
Barrett's esophagus (choice A) is characterized by the replacement of normal esophageal epithelium
with gastric-type epithelium. Barrett's causes an increased risk for adenocarcinoma, not bleeding.
37
Helicobacter gastritis (choice B) does not usually cause profuse bleeding.
Schatzki rings (choice D) are benign mucosal rings at the squamocolumnar junction below the aortic
arch.
Zenker's diverticula (choice E) are esophageal evaginations at the junction of the pharynx and
esophagus. They are not typically associated with bleeding.
79
78. Which of the following clinical conditions is most likely to result in hoarseness during
speech?
A. Right lung apical segment bronchogenic carcinoma
B. Congestive heart failure
C. Emphysema
D. Pulmonary thromboembolism
E. Thymoma
The correct answer is A. A tumor of the apical segment of the upper lobe may impinge on the
recurrent laryngeal nerve because it ascends from the superior mediastinum to the root of the neck in
a groove between the trachea and esophagus. The recurrent laryngeal nerve supplies all intrinsic
muscles of the larynx except the cricothyroid.
Congestive heart failure (choice B) is associated with exertional dyspnea, fatigue, orthopnea,
paroxysmal nocturnal dyspnea, and rales. Speech patterns are often normal.
Emphysema (choice C) is a condition associated with dyspnea, often severe, in which the presence
of a cough is rare. Speech patterns are generally normal.
Pulmonary embolus (choice D) causes an obstruction to arterial blood flow of the lung, resulting in
infarction of the affected segment. It may also cause pleurisy, resulting in pain conveyed by intercostal
nerves.
Thymoma (choice E), or tumor of the thymus gland, may cause dyspnea (difficulty breathing) caused
by pressure on the trachea. It may also cause engorgement of deep and superficial veins of the neck
caused by pressure on the superior vena cava.
80
```
79. Which of the following features characterizes apoptosis but not necrosis?
A. Disaggregation of polyribosomes
B. Eosinophilia
C. Inflammation
D. Karyolysis
E. Peripheral aggregation of chromatin
```
during development, maintain cell numbers in intact organs or tissues, and eliminate immune cells
after an immune response has faded. Apoptosis also occurs in response to noxious agents and in the
aging process by way of execution of a genetic program. In the process of apoptosis, cells shrink and
cytoplasmic organelles become more densely packed. Cytoplasmic blebs may form, and apoptotic
bodies (membrane-bound cellular fragments) can be produced. The most characteristic feature of
apoptosis is a distinctive peripheral aggregation of chromatin, sometimes accompanied by breaking
up of the nucleus into several fragments. In necrosis, the chromatin may become more pale
(karyolysis; choice D), or form irregular clumps, and the nucleus itself may shrink into a dense
pyknotic body.
Disaggregation of polyribosomes (choice A) is characteristic of the initial stages of cellular injury and
necrosis.
Eosinophilia (choice B) characterizes both apoptosis and necrosis.
38
Inflammation (choice C) is typically absent in apoptosis, in contrast to necrosis.
81
80. Which of the following can occur in a child after an upper respiratory infection who starts
to form multiple petechial hemorrhages and blood tests show marked reduction in platelets?
A. Idiopathic thrombocytopenic purpura
B. Iron deficiency anemia
C. Pernicious anemia
D. Von Willebrand's disease
The correct answer is A. The process described is commonly called acute idiopathic
thrombocytopenic purpura (ITP), even though the autoimmune basis has been clearly established
(some investigators use "immune thrombocytopenic purpura," so that the initials still work). The
thrombocytopenia in this disorder seems to be secondary to splenic destruction of opsonized platelets
and usually follows a viral upper respiratory tract infection. The acute form of ITP is usually explosive
but self-limited; a chronic form in adults may respond to steroid therapy or splenectomy.
Iron deficiency anemia (choice B) is almost always caused by bleeding in adults. Absent bone
marrow iron stores are noted or serum ferritin is low.
Pernicious anemia (choice C) is a macrocytic anemia with macro and hyposegmented neutrophils on
peripheral blood smear.
In von Willebrand's disease (choice E), deficient von Willebrand's factor produces platelet
dysfunction, but thrombocytopenia is not prominent.
82
```
81. Patients with Plummer-Vinson syndrome are at an increased risk for
A. Adenocarcinoma of the esophagus
B. Barrett's esophagus
C. Candida infection
D. Cytomegalovirus esophagitis
E. Squamous cell carcinoma of esophagus
```
The correct answer is E. Plummer-Vinson syndrome is characterized by atrophic glossitis,
esophageal webs, and iron-deficiency anemia. Patients with this syndrome are at increased risk for
developing squamous cell carcinoma of the esophagus.
Barrett's esophagus (choice B) and adenocarcinoma of the esophagus (choice A) are associated
with reflux esophagitis.
Candida (choice C) and cytomegalovirus (choice D) esophagitis can be seen in immunosuppressed
patients, including AIDS patients.
83
```
82. What is a flesh-colored lesion that presents on the nose that is 1 cm in diameter with
induration and central ulceration?
A. Basal cell carcinoma
B. Eczema
C. Psoriasis
D. Urticaria
E. Verruca vulgaris
```
The correct answer is A. The description is typical for basal cell carcinoma. These skin cancers
typically occur on sun-exposed areas of the head, neck, and upper trunk. Basal cell carcinoma only
rarely metastasizes, but can become locally mutilating if neglected. When located on the face, it may
be difficult to adequately excise without damaging facial structures.
39
Eczema (choice B) typically involves a larger area of skin and may cause dryness, discoloration, and
thickening of the involved area. Blistering, erythema, or oozing may also be observed.
Psoriasis (choice C) is characterized by erythematous plaques with a silvery surface.
Urticaria (choice D) causes transient, nonpitting, erythematous wheals.
Verruca vulgaris (choice E), the common wart, causes well-demarcated verrucous papules, often on
the hands.
84
```
83. Which of the following is may cause sudden extreme hematemesis and eventual loss of
consciousness?
A. Esophageal varices
B. Mallory-Weiss tear
C. Barrett's esophagus
D. Schatzki ring
E. Zenker's diverticulum
```
The correct answer is A. This is a description of life-threatening bleeding from esophageal varices
(tortuous, dilated, submucosal esophageal vessels). Sclerotherapy of the vessels and pressure on the
bleeding site with an "esophageal balloon" may temporarily control the problem, but unfortunately
bleeding often recurs and exsanguination is a frequent cause of death in these patients.
In contrast, Mallory-Weiss tears (choice B) occur as a complication of repeated vomiting and do not
often result in this amount of blood loss.
The other esophageal conditions listed do not usually cause hematemesis.
Barrett's esophagus (choice C) does not produce specific symptoms. Associated symptoms,
however, are generally a consequence of gastroesophageal reflux disease.
Schatzki rings (choice D) are benign mucosal rings found at the squamocolumnar junction of the
esophagus, below the aortic arch.
Zenker's diverticulum (choice E) is an esophageal evagination at the junction of the pharynx and
esophagus.
85
84. Which of the following characteristics is typical in the early stages of type 1 diabetes
mellitus, but not the early stages of type 2 diabetes mellitus?
A. Adult onset
B. Nearly complete twin concordance
C. Increased serum insulin levels
D. Ketoacidosis
E. Obesity
The correct answer is D. Type 1 diabetes mellitus, previously known as juvenile onset, is caused by
low insulin production as a consequence of autoimmune destruction of pancreatic beta cells. Severe
insulin deficiency causes marked increases in the use of fats as a source of energy. Ketones,
acetoacetate, and beta-hydroxybutyrate are produced in excess, and diabetic ketoacidosis may
develop with potentially dire consequences. Type 2 diabetes (or adult onset) is a consequence of
insulin resistance by the tissues, despite very high levels of serum insulin, initially (insulin levels
typically decrease as the disease progresses). Ketoacidosis is highly unusual in type 2 in the early
stages, because insulin is present. As the disease progresses, however, and insulin levels begin to
decrease, the incidence of ketoacidosis increases.
40
In type 1 there is usually complete loss of beta cells by puberty; thus, insulin dependence generally
begins in childhood. Type 2 usually has an adult age of onset (choice A).
There is approximately 50% twin concordance in type 1, suggesting that environmental factors must
also play a "triggering role" in type 1. The twin concordance rate is much higher in type 2 (~90%)
(choice B).
Insulin levels are nearly zero in type 1. Conversely, type 2 is a disease of insulin resistance and is
usually associated with increased insulin levels (choice C).
Body weight has no bearing on the pathogenesis of type 1, whereas type 2 occurs predominantly in
the obese (choice E).
86
```
85. Which of the following tests should be performed on a young adult woman who presents
with with fatigue, malaise, low-grade fever, arthralgias, elevated BUN, proteinuria, and butterfly
rash on her face?
A. Anticentromeric antibody
B. Antimitochondrial antibody
C. Antinuclear antibody
D. Anti-TSH receptor antibody
E. Rheumatoid factor
```
The correct answer is C. Systemic lupus erythematosus (SLE) and should be considered in any 15-
45-year-old woman with a malar (butterfly) rash, anti-double-stranded DNA antibodies, and renal
involvement. Antinuclear antibody is a good screening test (although it is also positive in some other
autoimmune diseases). Renal involvement is unique to this autoimmune disease. SLE mainly occurs
in young women and joint symptoms are seen in 90% of all patients. The most common features of
SLE include: malar rash, discoid rash, photosensitivity, oral ulcers, arthritis, serositis, renal disease,
neurologic disease, and positive ANA.
Anticentromeric antibody (choice A) is a marker for the CREST form of scleroderma.
Antimitochondrial antibody (choice B) is a marker for primary biliary cirrhosis. Anti-TSH receptor
antibody (choice D) is a marker for Grave's disease. Rheumatoid factor (choice E) is a marker for
rheumatoid arthritis.
87
87. A patient has intermittent diarrhea and abdominal pain and begins to pass fecal material in
his urine. Which of the following diseases is most likely to cause this complication?
A. Celiac disease
B. Crohn disease
C. Diverticulitis
D. Pseudomembranous colitis
E. Ulcerative colitis
The correct answer is B. Passing fecal material in urine strongly suggests the possibility of a fistula
between the bowel and bladder. Of the diseases listed, only Crohn disease (a type of inflammatory
bowel disease) commonly produces fistulas. Fistulas are produced in Crohn disease because the
disease affects the entire thickness of the bowel wall rather than being restricted to the mucosa (e.g.,
ulcerative colitis - choice E).
Celiac disease (choice A) is a mucosal disorder of the small intestine caused by intolerance to certain
components of gluten from wheat and other grains.
Diverticulitis (choice C) can cause bowel perforation with peritonitis but does not usually cause fistula
formation.
Pseudomembranous colitis (choice D), or antibiotic induced colitis, is usually caused by the toxin
produced by the bacteria Clostridium difficile. The most common complaint is severe diarrhea.
88
88. A patient's complete blood count demonstrates a hematocrit of 62%. The peripheral smear
shows normocellular erythrocytes, with increased reticulocytes and nucleated red cells. Bone
marrow biopsy demonstrates increased numbers of erythrocytic precursors. Cancer of which
of the following organs would be most likely to cause these findings?
A. Colon
B. Kidney
C. Ovary
D. Prostate
E. Thyroid
The correct answer is B. This is a pathophysiology question that can be answered easily by simply
understanding that a low hematocrit is probably caused by a low production of erythropoietin that is
synthesized and secreted in the kidney. The hematologic finding is erythrocytosis, which can be
caused by abnormal erythropoietin secretion by renal cell carcinoma (i.e., a paraneoplastic
syndrome). Absolute erythrocytosis also occurs in several other conditions, such as hypoxia, other
types of renal disease, some tumors (e.g., hepatocellular carcinoma, meningioma,
pheochromocytoma, cerebellar hemangioblastoma, adrenal adenoma), androgen therapy, Bartter
syndrome, or in polycythemia vera. Cancers of the colon (choice A), prostate (choice D), and thyroid
(choice E) do not usually produce inappropriate hormones. Cancers of the ovary (choice C) can
produce male or female sex steroids, but do not produce erythropoietin.
89
89. Arthritis with a history significant for morning stiffness and symmetric deformities of the
affected joints is most likely associated with which condition?
A. Ankylosing spondylitis
B. Gouty arthritis
C. Osteoarthritis
D. Rheumatoid arthritis
E. Septic arthritis
The correct answer is D. Involvement of the cervical spine occurs in almost 80% of patients with
rheumatoid arthritis and involves the atlanto-axial joint in up to 25% of those hospitalized for
rheumatoid arthritis. Fortunately, large degrees of subluxation of the joint are rare, but if present can
be associated with quadriplegia and even sudden death if the odontoid peg separates from the arch of
the atlas and compresses the spinal cord. The onset of rheumatoid arthritis is usually insidious and in
the small joints. Progression is centripetal and symmetric. Deformities are common. Extraarticular
manifestations include subcutaneous nodules, pleural effusion, pericarditis, lymphadenopathy, and
splenomegaly.
Serious complications of ankylosing spondylitis (choice A) include atrioventricular block, bladder and
bowel dysfunction, uveitis, pulmonary fibrosis, psoriasis, and inflammatory bowel disease.
Serious complications of gout (choice B) include renal impairment.
Serious complications of osteoarthritis (choice C) are uncommon, but the local manifestations can be
crippling. They do not cause quadriplegia. Pain and stiffness are most extreme at the end of the day,
which differs from rheumatoid arthritis.
Serious complications of septic arthritis (choice E) include joint destruction, osteomyelitis, and
systemic infection.
90
90. Which of the following can predispose a women to have vaginal itchiness and white curdy
discharge that upon microscopic examination demonstrates fungal hyphae and yeast forms?
A. Crohn's disease
B. Diabetes mellitus
C. Disseminated gonococcal infection
D. Rheumatoid arthritis
E. Systemic lupus erythematosus
The correct answer is B. The patient has vulvovaginitis secondary to Candida infection.
Predisposing factors include a high vaginal pH, diabetes, and use of antibiotics. The increased
vulnerability in patients with diabetes may reflect increased glucose concentrations in vaginal
secretions and relative immunosuppression, both of which provide an excellent environment for
fungus to grow.
Crohn's disease (choice A) can predispose for fistulas involving the vagina, rather than vulvovaginitis.
Dissemination of Neisseria gonorrhoeae (choice C) can cause septic arthritis.
Neither rheumatoid arthritis (choice D) nor systemic lupus erythematosus (choice E) are specifically
associated with Candida vulvovaginitis.
91
```
91. Which of the following most likely precedes the development of non-Hodgkin's lymphoma
in the gland?
A. Follicular thyroid carcinoma
B. Grave's disease
C. Hashimoto's thyroiditis
D. Nodular goiter
E. Papillary thyroid carcinoma
```
The correct answer is C. Hashimoto's disease (autoimmune thyroiditis) confers a 60-80-fold
increased risk for developing thyroid lymphoma. This increased risk is not surprising considering the
histology exhibited in Hashimoto's disease, in which sheets of benign but activated lymphocytes
infiltrate and eventually destroy the thyroid gland, producing eventual thyroid failure.
Neither follicular (choice A) nor papillary (choice E) thyroid carcinomas predispose for lymphoma.
Lymphoma is not related to Grave's disease (choice B) or benign nodular goiter (choice D).
92
92. Which of the following most likely describes a person who is pleasant, emotionally warm
and happy, lives at home, works in a sheltered workshop, did not complete high school, and
talks in three-word sentences?
A. Autistic disorder
B. Mental depression
C. Mental retardation
D. Mixed receptive-expressive language disorder
E. Parkinson's disease
The correct answer is C. This describes simple mental retardation.
Autistic disorder (choice A) is not correct because persons with this are rarely able to interact with
others to the point of holding a job, and they characteristically do not use language for purposes of
communication.
Mental depression (choice B) is associated with feelings of worthlessness and helplessness. It
generally does not affect speech patterns.
Mixed receptive-expressive language disorder (choice D) is a neurologic condition and affects
language skills. This description does not discuss the use of both receptive and expressive language
skills used to the point of being productively employed.
Parkinson's disease (choice E) is associated with postural instability, bradykinesia, and mask-like
facies. It does not affect cognitive function.
93
```
93. If polydipsia and polyuria are present, but without glycosuria, which of the following
should be considered?
A. Addison's disease
B. Diabetes insipidus
C. Diabetes mellitus
D. Grave's disease
```
The correct answer is B. Diabetes insipidus is characterized by the excretion of abnormally large
volumes of dilute urine (polyuria) with a commensurate increase in fluid intake (polydipsia). The most
common type is caused by inadequate secretion of antidiuretic hormone (also called vasopressin) and
is usually referred to as "neurogenic" diabetes insipidus. This condition rarely causes severe problems
as long as the person has plenty of water to drink. Placing a patient on overnight water restriction can
cause severe dehydration and a greatly elevated plasma sodium concentration. The possibility of
diabetes mellitus (choice C), which can also be associated with polyuria and polydipsia, but it does
not have glucosuria.
Addison's disease (choice A) results from failure of the adrenal cortices to produce adrenocortical
hormones. The lack of aldosterone leads to decreases in sodium reabsorption allowing large amounts
of sodium to be lost into the urine. Polyuria and polydipsia are not characteristic of Addison's disease.
Grave's disease (choice D) or thyrotoxicosis is associated with marked tachycardia, profuse
sweating, delirium, nausea, vomiting, and fever.
94
94. Microscopically, which of following do the proliferating cells in Kaposi's sarcoma
associated with HIV infection MOST closely resemble?
A. Angiosarcoma
B. Carcinosarcoma
C. Lymphoma
D. Malignant fibrous histiocytoma
E. Melanoma
The correct answer is A. Kaposi's sarcoma is a spindle cell neoplasm that is highly associated with
AIDS and with the Herpes simplex virus type 8. The tumor has an appearance similar to that of
angiosarcoma-proliferating stromal cells and endothelium, creating vascular channels that contain
blood cells.
Carcinosarcoma (choice B) is a tumor that contains malignant epithelial cells and malignant stromal
cells. There is no epithelial element in Kaposi's sarcoma.
Although lymphoma (choice C) occurs with increased frequency in AIDS, it does not resemble
Kaposi's sarcoma. Lymphoma involves neoplastic lymphocytes, whereas Kaposi's sarcoma involves
neoplastic vascular structures.
Malignant fibrous histiocytoma (MFH); (choice D) is an extremely poorly differentiated (anaplastic)
stromal malignancy. MFH does not produce any recognizable mesenchymal structures; thus, the
production of vascular structures by Kaposi's sarcoma differentiates the two tumors.
Melanoma (choice E) does produce colored skin lesions; however, the histologic appearance of the
malignant melanocytes is unlike Kaposi's sarcoma. Melanoma in situ appears as small nests of cells
with large, red nucleoli in the dermis and epidermis; this lesion can progress to a variety of forms, but
none resemble Kaposi's sarcoma.
95
95. What is the cause for the anemia that develops in a person with systemic lupus
erythematosus, chronic renal failure, and with a slightly yellow sclerae, enlarged spleen and
positive Coombs test?
A. Bone marrow aplasia
B. Antibody directed against red blood cells
C. Spleen sequestration
D. Renal failure
The correct answer is B. The anemia must be a hemolytic form, because it is associated with
unconjugated hyperbilirubinemia (hence the yellow sclerae), resulting from increased destruction of
red blood cells. Increased erythrocyte destruction is the cause (not the effect) of splenomegaly. A
positive Coombs test implies that hemolysis is mediated by antibodies attached to red blood cells.
Antibody-coated red cells are then sequestered by the spleen, where hemolysis occurs, thus
explaining splenomegaly.
Bone marrow aplasia (choice A) is caused by failure or suppression of myeloid stem cells, with
decreased production of red blood cells, platelets, and leukocytes (pancytopenia).
Spleen sequestration (choice C) may cause anemia in case of massive splenomegaly because of an
exaggeration of the normal role of the spleen as repository of blood cells.
Renal failure (choice D) causes normochromic, normocytic anemia because of decreased synthesis
of erythropoietin. Erythropoietin administration is currently the standard treatment for this form of
anemia.
96
96. Autoantibodies to which of the following components would most likely be found in a
person who is not taking any medications but has multiple oral ulcers and flaccid skin bullae
that were biopsied and showed a separation of epithelial cells above the basal layer?
A. Epidermal basement membrane proteins
B. Glycoprotein IIb/IIIa
C. Intercellular junctions of epidermal cells
D. Intrinsic factor
E. Type IV collagen
The correct answer is C. Bullae with the cleavage plane above the basal layer of the epidermis
suggests pemphigus vulgaris, which is caused by autoantibodies to intercellular junctions of epidermal
cells. The autoantibodies decrease the ability of the keratinocytes to adhere to one another, permitting
formation of vesicles and bullae. Oral involvement is common, and often precedes the characteristic
45
skin lesions. There will also be separation of the epidermis on manual stroking of the skin which is
known as Nikolsky's sign. This sign is present in other disorders such as Stevens-Johnson syndrome,
but we are told this person is healthy, and thus is not taking any medications, a typical cause of
Stevens-Johnson syndrome in the adult population.
Antibodies to epidermal basement membrane proteins (choice A) are seen in bullous pemphigoid,
which is a bullous disease characterized by blisters with a cleavage line between the epidermis and
dermis.
Antibodies to glycoprotein IIb/IIIa (choice B) are seen in autoimmune thrombocytopenic purpura.
Antibodies to intrinsic factor (choice D) are seen in pernicious anemia.
Antibodies to Type IV collagen (choice E) are seen in Goodpasture syndrome.
97
97. Which of the following is the reason for a CBC with reticulocyte count that shows very low
white blood cells and platelet counts, as well as having a bone marrow biopsy that
demonstrates cellularity less than 25%?
A. Anemia of chronic disease
B. Aplastic anemia
C. Myelodysplasia with myelofibrosis
D. Pure red cell aplasia
The correct answer is B. Aplastic anemia is characterized by pancytopenia (low levels of all blood
cells and platelets). Bone marrow biopsy typically reveals a normal architecture with a decrease in
cellularity to levels less than 25% of normal. Absolute neutrophil counts are also often extremely low.
Aplastic anemia may be either hereditary or acquired. Chloramphenicol, some anticonvulsant drugs,
phenylbutazone, and a variety of other agents may produce aplastic anemia in an idiosyncratic
manner. Aplastic anemias have also been linked to exposure to environmental toxins, such as
benzene and insecticides, and are often found to be preceded by viral infections from
cytomegalovirus, parvovirus, and hepatitis.
Anemia of chronic disease (choice A) produces an isolated deficit of red cell production and may
resemble iron deficiency.
The myelodysplastic syndromes (e.g., myelodysplasia with myelofibrosis, choice C) are characterized
by replacement of the bone marrow with abnormal (dysplastic) stem cells and ineffective
hematopoiesis.
Pure red cell aplasia (choice D) would produce a selective deficit of the erythrocytic lineage, not all
three lineages.
98
```
98. Which of the following should a person be evaluated for if they have rheumatoid arthritis
and suddenly develop moderate caries?
A. Diabetes insipidus
B. Polyarteritis nodosa
C. Sjogren's syndrome
D. Systemic lupus erythematosus
```
The correct answer is C. Rheumatoid arthritis can coexist with a variety of autoimmune diseases
(including those listed in the answers), but is most frequently associated with Sjogren's syndrome.
Sjogren's syndrome is caused by autoimmune involvement with subsequent scarring of the salivary
and lacrimal glands, leading to dry eyes and dry mouth. Secondary effects include parotid gland
enlargement, dental caries (from dry mouth or xerostomia), and recurrent tracheobronchitis.
Diabetes insipidus (choice A) is associated with polyuria and polydipsia but not dental caries.
Polyarteritis nodosa (choice B) is a systemic necrotizing vasculitis. Patients present with low-grade
fever, weakness, and weight loss. They may also have abdominal pain, hematuria, renal failure,
hypertension, and leukocytosis.
46
Systemic lupus erythematosus (choice D) is an autoimmune disease characterized by vasculitis
(which may produce a variety of symptoms depenThe correct answer is C. Rheumatoid arthritis can coexist with a variety of autoimmune diseases
(including those listed in the answers), but is most frequently associated with Sjogren's syndrome.
Sjogren's syndrome is caused by autoimmune involvement with subsequent scarring of the salivary
and lacrimal glands, leading to dry eyes and dry mouth. Secondary effects include parotid gland
enlargement, dental caries (from dry mouth or xerostomia), and recurrent tracheobronchitis.
Diabetes insipidus (choice A) is associated with polyuria and polydipsia but not dental caries.
Polyarteritis nodosa (choice B) is a systemic necrotizing vasculitis. Patients present with low-grade
fever, weakness, and weight loss. They may also have abdominal pain, hematuria, renal failure,
hypertension, and leukocytosis.
46
Systemic lupus erythematosus (choice D) is an autoimmune disease characterized by vasculitis
(which may produce a variety of symptoms dependepending on the site of the lesion), rash, renal disease,
hemolytic anemia, and neurologic disturbances.
99
99. Which of the following physical findings would be the MOST reliable indicator that an older
woman with shortness of breath is experiencing heart failure?
A. A third heart sound (S3)
B. A fourth heart sound (S4)
C. Ascites
D. Orthopnea
E. Pulmonary rales
The correct answer is A. A third heart sound (S3) is a low-pitched sound occurring at the termination
of rapid filling. In patients over 40 years of age, the appearance of a third heart sound strongly
suggests congestive heart failure. It also occurs in patients with atrioventricular valve incompetence
and can be a normal finding in some young athletes. Other common signs and symptoms of heart
failure include the following:
Left ventricular failure: exertional dyspnea, fatigue, orthopnea, cough, cardiac enlargement, rales,
gallop rhythm, and pulmonary venous congestion.
Right ventricular failure: elevated venous pressure, hepatomegaly, and dependent edema.
A fourth heart sound (S4; choice B) can be a normal finding in some older patients who do not have
congestive heart failure.
Ascites (choice C) can also occur in patients with renal, hepatic, or local conditions not associated
with cardiac factors.
Both orthopnea (choice D) and pulmonary rales (choice E) often occur secondary to heart failure;
however, they both are associated with noncardiac disorders also.
100
100. Which of the following is an example of a type II hypersensitivity?
A. Cutaneous reactions to drugs
B. Heat intolerance, sinus tachycardia, and proptosis caused by endocrine disease
C. Eczematous reaction on the dorsum of the foot after new detergent use
D. Glomerulonephritis with systemic lupus erythematosus
E. Wheal and flare reactions and vesicles due to fire ant bites
The correct answer is B. Type II hypersensitivity is mediated by antibodies directed toward antigens
that are present on the surface of cells or other tissue components. The antigen may be intrinsic to
the cell membrane or may take the form of an exogenous antigen that is adsorbed to the cell surface.
The situation described is Grave's disease, which is an autoimmune form of hyperthyroidism
produced by autoantibodies directed against the TSH (thyroid stimulating hormone) receptor. These
antibodies are called LATS (long-acting thyroid stimulator) and stimulate thyroid function, resulting in
the release of thyroid hormones.
A drug reaction (choice A) and wheal and flare reactions (choice E) are cutaneous manifestations of
type I hypersensitivity. Certain allergens, especially drugs, insect venoms, latex, and foods may
induce a type I IgE antibody response.
An eczematous reaction (choice C) associated with washing clothes in a new detergent may either
represent type IV hypersensitivity or a nonimmune reaction associated with direct toxicity from some
component of the soap penetrating the skin.
Glomerulonephritis in systemic lupus erythematosus (choice D) is caused by the deposition of
antigens in the glomerular basement membrane with the resultant formation of antigen-antibody
47
complexes. These complexes activate the complement cascade, which causes neutrophils to enter
the area and produce tissue damage.
101
101. Examination of a peripheral blood smear demonstrates a leukemia composed of small
mature lymphocytes without blast forms. If a diagnosis of chronic lymphocytic leukemia is
made, which of the following is the most likely age of this patient?
A. 1 year
B. 5 years
C. 20 years
D. 45 years
E. 65 years
The correct answer is E. Different leukemias tend to affect populations of different ages. The
disease described is chronic lymphocytic leukemia (CLL), a disease of older adults.
Both the 1-year-old (choice A) and the 5-year-old (choice B) would be most likely to have acute
lymphocytic leukemia (ALL).
The 20-year-old (choice C) would be most likely to have acute myelocytic leukemia (AML).
The 45-year-old (choice D) would be likely to have either AML or chronic myelogenous leukemia
(CML).
102
```
102. Which of the following serum chemistry studies will MOST likely be abnormal in a
preteen with polydipsia that develops weight loss despite eating large amounts of food over a
three month period?
A. Blood urea nitrogen
B. Serum bicarbonate
C. Serum calcium
D. Serum glucose
E. Serum sodium
```
The correct answer is D. Although it is commonly known that diabetes mellitus is associated with
polyuria and polydipsia, many do not realize it is also associated with weight loss despite increased
eating, also known as polyphagia. In our extremely weight- and food-conscious society, this
phenomenon may be much more striking to the patient and his family than a change in the amount of
fluid intake. The lesson learned is that a child who develops weight loss despite increased food intake
should have a blood glucose test.
All of the other answer choices would be expected to be normal in this patient.
103
103. Which of the following is involved in hypoxia in a smoker with noticeable increase in
anteroposterior chest width if oxygen therapy is effective?
A. Anemia caused by blood loss
B. Edematous tissues
C. Emphysema
D. Localized circulatory deficiencies
E. Right-to-left cardiac shunts
The correct answer is C. Chronic pulmonary emphysema is characterized by distention of small air
spaces distal to the respiratory bronchioles and destruction of alveolar septa. Long-term cigarette
smoking is the usual cause. The marked loss of lung parenchyma associated with emphysema leads
to a decrease in the diffusion capacity of the lungs that reduces their ability to oxygenate blood and
remove carbon dioxide, contributing to the "barrel chest" appearance of these patients. Cigarettes
also inhibit Alpha-1 antitrypsin allowing trypsin to break down proteins in the alveoli. When arterial
hypoxemia is persistent and severe, oxygen therapy should therefore be considered.
48
Oxygen therapy is less effective for treating the hypoxia associated with anemia (choice A),
edematous tissues (choice B), localized circulatory deficiencies (choice D), and right-to-left cardiac
shunts (choice E), because in each case, there is already adequate oxygen available in the alveoli.
The problem in each of these situations is inadequate transport of oxygen to the tissues, blunting the
effects of increasing the oxygen tension of the inspired air. Oxygen therapy nonetheless increases the
amount of dissolved oxygen carried in the blood, which may be life-saving in some instances.
104
```
104. Which of the following characterizes an eczematous reaction that occurs 72 hours after
wearing latex gloves?
A. Irritant dermatitis
B. Type I reaction
C. Type II reaction
D. Type III reaction
E. Type IV reaction
```
The correct answer is E. Sensitization to latex has become a major healthcare problem. Local skin
irritations are common but more severe allergic reactions occur, up to and including rare anaphylactic
reactions that are occasionally fatal. The immune responses to latex are immediate-type
hypersensitivity (type I) reactions, expressing themselves in minutes, or delayed-type hypersensitivity
(type IV) reactions that express themselves in 48-72 hours. The type I reactions are caused by the
IgE-mediated sensitivity to latex proteins, whereas the type IV reactions are caused by a cellmediated
response to the chemicals that are added in the processing of latex. The type IV response
in this circumstance would be referred to as contact dermatitis.
Irritant dermatitis (choice A) can be observed in the early stages of sensitization and can be caused
by sweating, rubbing, and residual soap. The timing of the reaction after 72 hours points to the type IV
reaction rather than an irritant dermatitis.
A type I reaction (choice B) would have been apparent within minutes with characteristic rhinitis,
conjunctivitis, urticaria, asthma, angioedema, or anaphylaxis immediately after wearing latex gloves.
A type II reaction (choice C) is a cytolytic response mediated by an antibody. The type II reaction is
observed in the context of hemolytic anemias, thrombocytopenia, and neutropenia.
A type III reaction (choice D) is an immune-complex response that sets into motion an inflammatory
response.
105
105. What is the explanation for an older person having a fainting spell with a resting blood
pressure of 130/60 mm Hg and a pulse reading of 40 beats per minute?
A. Aortic valve obstruction
B. Cardiac tamponade
C. Complete heart block
D. Heart failure
E. Hypertension
The correct answer is C. In complete (third degree) heart block, the ventricles beat independently of
SA node activity and P waves become completely dissociated from QRS-T complexes. The rate of the
ventricular beat is usually 30-45 per minute. Because resting cardiac output (CO) is normal and
because CO = stroke volume x heart rate, the stroke volume is increased in complete heart block.
When the stroke volume increases, a greater amount of blood must be accommodated in the arterial
tree with each heartbeat, which causes a greater increase and decrease in pressure during systole
and diastole. Note that the pulse pressure is 70 mm Hg (normal pulse pressure is 30-50 mm Hg).
The pulse pressure is decreased in aortic valve obstruction (choice A), cardiac tamponade (choice
B), heart failure (choice D). This is clearly not hypertension (choice E).
106
106. A well-behaved toddler, accompanied by his parents, presents with multiple fractures,
humpback and blue sclera. What is the probable diagnosis?
A. Child abuse
B. Ehlers- Danlos syndrome
C. Osteogenesis imperfecta
D. Scurvy
The correct answer is choice C. Osteogenesis imperfecta, also known as Brittle bone disease, is
characterized by retarded wound healing. . The most common form is autosomal dominant with
abnormal collagen type 1 synthesis due to a mutation in the collagen gene.
Choice A- Child abuse is unlikely in this well-behaved toddler with no other signs and symptoms of
abuse. Blue sclera are also typical of osteogenesis imperfecta, and not related to child abuse.
Choice B- Mutation in the collagen gene and lysine hydroxylase gene results in hyperextensible,
fragile skin, hypermobile joints, dislocations, varicose veins, ecchymoses, and arterial intestinal
ruptures. Inheritance varies. There are 10 types with any one of several enzyme deficiencies.
Choice D- Scurvy is characterized by anemia, petechiae, ecchymoses, bleeding gums, loose teeth,
poor wound healing and poor bone development. Deficient hydroxylation of collagen due to vitamin C
deficiency results in defective connective tissue.
107
```
107. When a histologic section is taken of an intraoral abscess, many of the observed
neutrophils show a degenerative change in which the nucleus has undergone fragmentation.
This process is known as
A. caseous necrosis
B. coagulative necrosis
C. karyolysis
D. karyorrhexis
E. pyknosis
```
The correct answer is D. Karyorrhexis refers to a pattern of nuclear degradation in which a pyknotic
or partially pyknotic nucleus undergoes fragmentation followed by complete lysis. This pattern is
common in the neutrophils present in acute inflammation.
The type of necrosis seen in an abscess is liquefactive necrosis. Caseous necrosis (choice A) is
seen in tuberculosis and some other granulomatous diseases; coagulative necrosis (choice B) is
seen following infarctions of many organs (other than the brain).
Karyolysis (choice C) is also a degenerative change affecting nuclei. In this case, however, it is seen
as a decrease in nuclear basophilia, which is presumably the result of DNAse activity.
Pyknosis (choice E) is characterized by nuclear shrinking and basophilia, apparently as a result of
DNA condensation.
108
```
108. If hypocalcemia is noted, excessive secretion of which of the following hormones MOST
likely contributed to hand and forearm bone erosion and resorption during chronic renal
failure?
A. Aldosterone
B. Calcitonin
C. Parathyroid hormone
D. Renin
E. Vitamin D
```
The correct answer is C. In renal failure, the ability of the kidney to secrete phosphate is impaired.
The resultant hyperphosphatemia causes hypocalcemia and triggers excretion of large amounts of
50
parathyroid hormone. The released parathyroid hormone is a major contributor to bony changes (e.g.,
osteitis fibrosa, a form of localized bone resorption) seen with chronic renal failure. Note that excess
parathyroid hormone normally causes hypercalcemia, but calcium resorption still cannot bring calcium
levels back to normal.
Aldosterone (choice A) is a regulator of serum sodium.
Calcitonin (choice B) levels are usually low in chronic renal failure unless the parathyroids have so
hypertrophied as to cause "tertiary hyperparathyroidism" with hypercalcemia.
Renin (choice D) is normally secreted by the kidney and may be decreased or increased in varying
stages and forms of kidney disease. Renin regulates blood pressure and aldosterone secretion, rather
than bone metabolism.
The active form of vitamin D (choice E), cholecalciferol, is formed in the kidney from vitamin D
absorbed from the gut and then processed by the liver. Uremia interrupts this pathway and
consequently causes a functional vitamin D deficiency.
109
109. Which of the following would be MOST likely present on a biopsy of a thyroid gland and
associated tissues that has a woody hardness when palpated but the needle biopsy shows no
evidence of malignancy?
A. Marked fibrous reaction with gland destruction
B. Masses of hyperplastic follicles
C. Multinucleated giant cells
D. Small foci of lymphocytic infiltration
E. Prominent lymphocytic infiltrate with gland destruction
The correct answer is A. With Riedel's thyroiditis, an uncommon form of chronic (possibly
autoimmune) thyroiditis that is characterized by dense fibrosis that destroys the thyroid gland and also
extends into the adjacent muscle and connective tissue of the neck. The condition is clinically
important because it may mimic malignancy. A key to the diagnosis is the woody hardness of fibrosis.
All other choices are likely to be swollen and soft by palpation.
Masses of hyperplastic follicles (choice B) are a feature of multinodular goiter.
Multinucleated giant cells (choice C) are a feature of de Quervain thyroiditis.
Lymphocytic infiltration (choice D) is a part of many thyroid diseases, but is seen in isolation in
subacute lymphocytic thyroiditis.
Sheets of lymphocytes with gland destruction (choice E) are seen in Hashimoto's thyroiditis.
110
110. Which of the following gastrointestinal diseases is most likely to be associated with
megaloblastic anemic who has been found to be deficient in vitamin B12, while the levels of all
other essential vitamins are within normal limits?
A. Atrophic gastritis
B. Celiac sprue
C. Duodenal ulcer
D. Ulcerative colitis
E. Zollinger-Ellison syndrome
The correct answer is A. An important cause of vitamin B12 deficiency is pernicious anemia
(megaloblastic), an autoimmune disease associated with atrophic gastritis. In atrophic gastritis, the
gastric epithelium undergoes intestinal metaplasia, replacing gastric chief and parietal cells with
goblet cells. The metaplastic epithelium produces insufficient intrinsic factor to bind the dietary vitamin
B12deficiency.
51
Celiac sprue (choice B) is a condition associated with weight loss, flatulence, greasy stools, and
increased fecal fat. Clinical improvement is seen with a gluten-free diet (a diet free of wheat, rye,
barley, and oats).
Duodenal ulcers (choice C) may also produce iron deficiency anemia because of chronic blood loss.
They are caused by damage to the duodenal epithelium by gastric acids and are associated with
cirrhosis, COPD, chronic renal failure, and hyperparathyroidism.
Ulcerative colitis (choice D) is an inflammatory bowel disease almost entirely restricted to the large
intestine. It usually causes intestinal distress and diarrhea, and it may produce a malabsorption
syndrome that includes vitamin B12deficiency.
Zollinger-Ellison syndrome (choice E) is caused by gastric acid hypersecretion leading to peptic ulcer
disease. Diarrhea is common.
111
```
111. If left untreated, severe squamous dysplasia on a vocal cord of a hoarse smoker may
progress to which of the following?
A. Adenocarcinoma
B. Lymphoepithelioma
C. Mucoepidermoid carcinoma
D. Squamous cell carcinoma
E. Squamous papilloma
```
The correct answer is D. Squamous cell carcinoma is the most frequent type of cancer of the larynx.
As with squamous cell carcinoma of the uterine cervix, the development of laryngeal carcinoma is
related to an orderly sequence of morphologic changes. These begin with epithelial hyperplasia,
proceed through increasingly severe degrees of dysplasia up to in situ carcinoma, and culminate with
invasive carcinoma. Cigarette smoking is the most important risk factor for the development of
laryngeal carcinoma. Any patient over the age of 50 years with hoarseness that has persisted beyond
2-3 weeks should be evaluated by indirect laryngoscopy. Odynophagia, hemoptysis, weight loss,
referred otalgia, vocal cord immobility and cervical adenopathy suggest more advanced disease.
Adenocarcinoma (choice A) and mucoepidermoid carcinoma (choice C) are rare forms of laryngeal
cancer. Squamous dysplasia is not a precursor of either type of tumor.
Lymphoepithelioma (choice B) is a form of squamous cell carcinoma that most frequently occurs in
the nasopharynx, although it has been reported in the larynx also. Its name is derived from the fact
the tumor is rich in lymphocytes. This tumor occurs frequently in southern China and certain regions in
Africa. Epstein-Barr virus is implicated in its pathogenesis.
Squamous papilloma (choice E) is a benign laryngeal neoplasm caused by human papillomavirus
types 6 and 11. It is not associated with squamous dysplasia.
112
```
112. What is the BEST explanation for the significant elevation of liver enzymes, ammonia, and
hypoglycemia experienced five days after the onset of chicken pox in a child that was given
aspirin for fever-control?
A. Crigler-Najjar syndrome
B. Dubin-Johnson syndrome
C. Gilbert's syndrome
D. Reye's syndrome
E. Rotor's syndrome
```
The correct answer is D. The use of aspirin in a child with chicken pox can cause Reye's syndrome.
Reye's syndrome (fatty liver with encephalopathy) is an acute (and potentially fatal) postviral injury
that is characterized by severe mitochondrial damage affecting the liver, brain, skeletal muscle, heart,
and kidneys. The rapidly progressive hepatic failure and encephalopathy is associated with a 30%
fatality rate. Most are children, although adult cases have been described. Varicella and influenza A
and B are the most common precipitating illnesses. Aspirin use has been linked to the development of
52
this disorder, but cases occur in the absence of salicylate ingestion. Hypoglycemia, elevated serum
aminotransferases and blood ammonia, prolonged prothrombin time, and change in mental status all
occur within 2-3 weeks after onset.
Crigler-Najjar (choice A) syndrome is a rare, mild to severe form of inherited unconjugated
hyperbilirubinemia.
Dubin-Johnson syndrome (choice B) is an inherited conjugated hyperbilirubinemia associated with a
darkly pigmented liver.
Gilbert's syndrome (choice C) is a common, benign form of inherited unconjugated
hyperbilirubinemia.
Rotor's syndrome (choice E) resembles Dubin-Johnson syndrome, but is associated with a normalcolored
liver.
Although most of these other symptoms are rare, it is important to recognize the signs, symptoms,
and causes of Reye's syndrome.
113
```
113. Which of the following is the MOST likely the reason for persistent and marked anasarca
noted with jaundice?
A. Lymphatic obstruction
B. Reduced central venous pressure
C. Reduced plasma oncotic pressure
D. Sodium retention
E. Venous thrombosis
```
The correct answer is C. Hepatic failure occurring in cirrhosis reduces the capacity of the liver to
synthesize sufficient quantities of plasma proteins (mostly albumin) necessary to maintain plasma
oncotic pressure. Low plasma oncotic pressure allows fluid from the intravascular fluid component to
move into the interstitial space, producing plasma volume contraction and edema.
Lymphatic obstruction (choice A) occurs as a result of mechanical blockage of lymphatics by tumor,
inflammatory processes, or certain parasitic infections. Cirrhosis does not lead to lymphatic
obstruction.
Reduced central venous pressure (choice B) does not cause edema. Conversely, increased central
venous pressure, which may arise with congestive heart failure, thrombosis, or cirrhosis can lead to
increased hydrostatic pressure and edema.
Sodium retention (choice D) is an important cause of edema in patients with poor renal perfusion.
The kidneys respond by retaining sodium and increasing plasma volume in an effort to increase renal
blood flow. Any sodium retention in cirrhosis is secondary to the decrease in plasma oncotic pressure
and consequent decrease in plasma volume.
Venous thrombosis (choice E) can lead to edema; however, the diminished synthesis of coagulation
proteins in cirrhosis predisposes to bleeding, not thrombosis.
114
```
114. What of the following is characterized by left lower quadrant periumbilical pain in an
elderly person, with the presence of fever, tender abdomen, leukocytosis, nausea, and
vomiting?
A. Acute appendicitis
B. Diverticulitis
C. Gallstones
D. Pancreatitis
E. Pyelonephritis
```
The correct answer is B. Diverticulitis is a disease of the elderly and usually involves the distal
colon. In severe cases, however, the diverticula may extend throughout the colon and up to the
cecum. Inflammation of a cecal diverticulum can closely mimic acute appendicitis. The essentials of
diagnosis for diverticulitis are acute abdominal pain and fever, left lower abdominal tenderness, and
mass. Leukocytosis is commonly present together with nausea and vomiting.
Acute appendicitis (choice A) is usually a disease of young adults (and sometimes children). It is
rarely seen in the elderly.
Pancreatitis (choice D), pyelonephritis (choice E), and gall bladder disease (choice C), refer pain to
the mid back, lateral back, and right upper quadrant, respectively.
115
115. Which of the following would most likely be associated with Type A chronic gastritis
resulting from autoimmune destruction of parietal cells?
A. Decreased growth of luminal bacteria
B. Decreased likelihood of developing gastric carcinoma
C. Decreased plasma concentration of gastrin
D. Increased production of macrocytic red blood cells
E. Increased secretion of pancreatic bicarbonate
The correct answer is D. Autoimmune destruction of parietal cells would lead to decreased secretion
of gastric acid and intrinsic factor. The diminished availability of intrinsic factor would result in poor
absorption of dietary vitamin B12. Over time, the vitamin B12 deficiency could lead to pernicious
anemia, which is characterized by increased production of macrocytes (megaloblasts) by the bone
marrow.
Because of the decrease in gastric acid secretion, luminal bacteria (choice A) would most likely
exhibit increased (not decreased) growth. One of the functions of HCl secreted by the parietal cells is
to sterilize the gastric lumen.
Patients with Type A gastritis have an increased likelihood of developing gastric carcinoma (not
decreased, choice B).
A decrease in acid secretion leads to increased secretion of gastrin (not decreased, choice C) by
antral G cells. This is because low gastric pH (less than 3.0) inhibits gastrin secretion by way of
paracrine release of somatostatin from cells in the gastric mucosa that can sense the acidity. With
decreased parietal cells, the pH of the gastric lumen would rise and remove this inhibitory component.
Because less acid would be delivered to the duodenum with parietal cell destruction, less secretin
would be released into the blood. This would result in decreased pancreatic bicarbonate secretion
(not increased, choice E).
116
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116. What is present in an older woman when there is increased serum levels of calcium and
urinary cAMP levels, below normal levels of serum phosphate, and no other complaints but
weakness?
A. A calcitonin-secreting tumor
B. Primary hyperparathyroidism
C. Primary hypoparathyroidism
D. Thyrotoxicosis
E. Vitamin D deficiency
```
The correct answer is B. Primary hyperparathyroidism is often asymptomatic and only incidentally
discovered during routine blood work, however, there may be vague complaints of fatigue or
weakness and constipation. These neuromuscular manifestations are caused by the hypercalcemia
that can "hyperstabilize" excitable tissue membranes and reduce normal responsiveness. Primary
hyperparathyroidism incidence increases greatly after age 50 years, and is more common in women
than men. The hypercalcemia is caused by the excess plasma concentration of parathyroid hormone
(PTH). Approximately 80% of cases are caused by a single adenoma in a parathyroid gland. In the
54
other 20% of cases, the hypersecretion of PTH is caused by hyperplasia in multiple parathyroid
glands. The increased PTH also causes renal excretion of phosphate, producing hypophosphatemia.
PTH acts by increasing cAMP formation in target tissues. The cAMP formed in renal tubules can
diffuse into the lumen and be measured in the urine.
Tumors that secrete calcitonin (choice A) include medullary carcinoma of the thyroid and occasionally
small and large cell carcinomas of the lung. Despite calcitonin's high blood concentration, serum
phosphate is rarely abnormal and calcium levels would decrease rather than increase.
Primary hypoparathyroidism (choice C), which is caused by decreased secretion of PTH, is
associated with hypocalcemia and hyperphosphatemia. Furthermore, urinary cAMP concentration
would be decreased. The low calcium in extracellular fluid "destabilizes" excitable tissue membranes
and can lead to spontaneous action potentials that produce tetany.
Thyrotoxicosis (choice D) or hyperthyroidism is associated with sweating, anxiety, heat intolerance,
irritability, fatigue, muscle weakness, tachycardia, and warm moist skin. With vitamin D deficiency
(choice E), serum calcium is decreased because of diminished absorption from the diet. PTH
secretion is increased to compensate, resulting in bone demineralization (osteomalacia).
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117. If there is a large retinal detachment in the right eye and nothing noted in the left, how do
the eyes react to a pupillary light reflex examination?
A. Constriction of the right pupil and constriction of the left
B. Constriction of the right pupil and dilatation of the left
C. Dilatation of the right pupil and constriction of the left
D. Dilatation of the right pupil and dilatation of the left
E. No reaction of the right pupil and constriction of the left
The correct answer is D. The eyes are exhibiting the Marcus-Gunn phenomenon. When light strikes
the retina, the pupillary light reflex is automatically triggered, leading to simultaneous constriction of
both pupils. In the absence of adequate light entering the eye, for example, following retinal
detachment or optic neuritis, paradoxic dilatation of the pupils occurs. The retina receives far less light
than it normally would, and the pupils dilate to absorb as much light as possible.
118
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118. Which of the following findings is particularly indicated with a marked elevation in serum
C-reactive protein?
A. Developing autoimmune reaction
B. Ineffective immune response
C. Respiratory compromise
D. Nonspecific inflammation
```
The correct answer is D. C-reactive protein is one of the most commonly measured acute-phase
reactants, which are a group of serum proteins showing a rapid increase in concentration in response
to any inflammatory process. This finding is entirely nonspecific. It only indicates a recent
inflammatory process. C-reactive protein would be expected to be elevated following a dental
procedure and in cases of pharyngitis (viral and bacterial).
An autoimmune reaction (choice A), which is certainly a concern with streptococcal pharyngitis, is
suggested by the development of a rising ASO (antistreptolysin O) titer weeks after the illness. Acute
phase reactants are not specific to autoimmune processes.
Increases in C-reactive protein indicate a healthy immune response to an infective pathogen. An
ineffective immune response (choice B) would not elicit acute-phase reactions.
Respiratory compromise (choice C) produces changes in arterial blood gases and blood pH. Acutephase
reactants do not reflect respiratory status.
119
119. Which of the following is characteristic when there is a blood pressure of 165/95 mm Hg,
tiredness, muscle weakness, polydipsia, while plasma sodium and serum aldosterone is
slightly increased and plasma potassium and plasma renin activity is significantly decreased?
A. Addison's disease
B. Conn's syndrome
C. Cushing's syndrome
D. Type 1 diabetes mellitus
E. Pheochromocytoma
The correct answer is B. Conn's syndrome, or primary hyperaldosteronism, results from an adrenal
tumor that secretes excessive aldosterone. The increased mineralocorticoid effects of aldosterone
lead to renal sodium and water retention (which explains the hypertension) and increased renal
potassium excretion (hypokalemia). The volume expansion also explains the decrease in hematocrit.
The increased blood volume, increased blood pressure, and hypernatremia all tend to suppress renin
secretion in an attempt to compensate for the increased aldosterone.
Addison's disease (choice A), or primary adrenal insufficiency, is characterized by low plasma
concentration of aldosterone, hyponatremia, hypotension, and hyperkalemia.
In Cushing's syndrome (choice C), blood pressure may be increased because of crossover
mineralocorticoid activity of the increased plasma cortisol. Furthermore, cortisol makes blood vessels
more responsive to catecholamines, which could increase peripheral resistance. The combination of
increased blood pressure and hypokalemia would, if anything, tend to suppress secretion of
aldosterone.
Type 1 diabetes mellitus (choice D) is associated with polyuria, polydipsia, muscle weakness, and
chronic tiredness. Renin and aldosterone levels are normal.
Pheochromocytoma (choice E) is another endocrine cause of hypertension. The increased plasma
concentration of catecholamines can cause increased cardiac output and increased peripheral
resistance. Plasma renin activity may be increased because of increased beta receptor activation on
juxtaglomerular cells. This could produce increased aldosterone secretion and subsequent salt
retention.
120
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120. Which of the following BEST describes the inflammatory response that occurs upon
contact with certain plants and presents as a weeping, vesicular, erythematous, and itchy rash
on exposed arms, legs, neck, and face?
A. Erythema nodosum
B. Pemphigus
C. Psoriasis
D. Spongiotic dermatitis
E. Urticaria
```
The correct answer is D. Spongiotic dermatitis (intracellular edema of the epidermis) is seen in with
contact dermatitis, such as poison ivy exposure. The accumulation of inflammatory cells in the
superficial dermis causes marked edema, which splays epidermal keratinocytes apart and gives a
spongy appearance to intercellular bridges. Grossly, the skin has a weepy appearance with frequent
blistering. Erythema nodosum (choice A) is a form of panniculitis, which is chronic inflammation in the
subcutaneous fat lobules. Erythema nodosum presents as painful erythematous nodules, often with
fever and malaise. It is associated with infections and drug reactions and is not a contact dermatitis.
Pemphigus (choice B) is a genetic blistering disorder caused by the production of antibodies to the
intercellular cement substances in skin and mucous membranes. Psoriasis (choice C) is a common
chronic inflammatory disease causing plaques and scales, typically on elbows, knees, and scalp. The
pathogenesis of psoriasis is still unclear; it may be a complement-mediated autoimmune process.
Urticaria (choice E) is an IgE-driven hypersensitivity process. Urticaria is characterized by wheals
(edematous pruritic plaques) and typically affects the trunk and distal extremities
