Study Guide Questions Ch 6

Question 1

Which of the following is the most abundant bronchospasm-inducing arachidonic acidderivative generated by cyclooxygenase in the mast cells?

a. Leukotriene B4
b. Prostacyclin
c. Prostaglandin D2
d. Thromboxane
e. Lipoxin

Answer 1

ANS: C,

Prostaglandin D2is the most abundant arachidonic acid derivative produced throughthe cyclooxygenase pathway. It causes bronchospasm and increased mucus productio

Question 2

A 40-year-old man presents with hemoptysis and renal failure. A kidney biopsy specimenrevealed linear deposits of IgG in glomerular basement membranes and crescents between the glomerular capillary loops and the Bowman capsule. The antibodies causing these pathologic changes react with..?

A. laminin 
B. Fibronectin
C. Collagen Type I
D. Collagen Type IV
E. Podocytes

Answer 2

D Collagen Type IV

This man has Goodpasture syndrome, in which the body produces autoantibodies to the
globular part of type IV collagen in the glomerular basement membranes and the lungs.

Question 3

Which antibody can most effectively activate complement by the alternate pathway, even without prior forming an antigen-antibody complex?

A. IgA
B. IgG
C. IgD
D. IgM
E. IgE

Answer 3

A IgA

IgA can activate complement by the alternate pathway.

Question 4

Antigen-antibody reaction in polyarteritis nodosa is characterized by which form of necrosis of the arterial wall?

A. Coagulative necrosis
B. Fibrinoid necrosis
C. Liquefactive necrosis
D. Fat necrosis
E. Caseous necrosis

Answer 4

B. Fibrinoid necrosis

Antigen-antibody complexes cause inflammation of the vessel wall, accompanied by the
insudation of plasma proteins into the site of injury. The necrosis is classified as
fibrinoid, because it contains large amounts of fibrin formed from fibrinogen in the
plasma insudated into the damaged vessel wall.

Question 5

A 23 y/o woman was given an intradermal injection of purified protein derivative of tubercle bacilli (PPD) as part of the yearly testing for tuberculosis. A positive reaction was elicited. Which cells secrete the cytokines needed for the formation of granulomas at the site of injection?
A. Keratinocytes
B. Melanocytes
C. B Lymphocytes
D. TH1 cells
E. TH2 cells

Answer 5

D Granuloma formation depends on cytokines produced by TH1 cells derived from CD4+ lymphocytes

Question 6

The formation of vesicles in contact dermatitis caused by poison ivy is primarily mediated by:
A. TH1 lymphocytes
B. TH2 lymphocytes
C. CD8 lymphocytes
D. B cells 
E. macrophages

Answer 6

A.

TH1 helper lymphocytes accumulate first at the site of exposure to the foreign antigen in the skin; they also are the most important mediators of epidermal cell injury that leads to
formation of vesicles and bullae. CD8 cytotoxic cells also take part in later stages of the reaction, but to a lesser degree.

Question 7

Generic antinuclear antibodies are found in more than 95% of patients with systemic lupus erythematosus. Which pattern of staining seen on tissue culture cells in the indirect antibody immunofluorescence microscopy test signifies the presence of these antibodies?
A. Nucleolar pattern
B. Speckled nuclear pattern
C. Diffuse nuclear pattern
D. Rim nuclear pattern
E. Granular cytoplasmic pattern

Answer 7

C.

Generic antinuclear antibodies (ANA) reacting with chromatin, histones, and
occasionally double-stranded DNA give a diffuse nuclear staining pattern. Rim (or
peripheral) staining is due to antibodies to double-stranded DNA. A speckled pattern is typical of antibodies to non-DNA nuclear components, including the Sm-antigen, which is the most specific marker of systemic lupus erythematosus. A nucleolar pattern reflects the presence of antibodies to nucleolar RNA. Cytoplasmic staining is nonspecific and
unrelated to antinuclear antibodies.

Question 8

The most common and most serious form of renal disease encountered in lupus (SLE) is classified as x. Most of the lesions found in SLE are mediated by deposition of immune complexes (type III hypersensitivity rxn). Which pathologic reaction is due to the type II hypersensitivity (cytotoxic) reaction?

A. Class I (minimal changes)
B. Class II (mes angial)
C. Class III (focal proliferative)
D. Class IV (diffuse prolierative)
E. Class IV (membranous)

Answer 8

D

The most common and clinically the most serious form of lupus nephritis is class IV,
diffuse proliferative glomerulonephritis.

Question 9

Which of the following is the predominant and most common cardiovascular manifestation of SLE?

A. mural endocarditis
B. Valvular endocarditis
C. myocarditis
D. pericarditis
E. conduction system injury

Answer 9

D

Pericarditis is the most common cardiovascular manifestation of systemic lupus erythematosus.

Question 10

Which antibodies are considered to be markers of Sjogren syndrome?

A. Antinuclear antibody
B.  Anti-double-stranded DNA
C. Anti-single-stranded DNA
D. Anti- topoisomerase
E. Anti-ribonucleoprotein antibody SS-A (Ro)

Answer 10

E.

Anti-ribonucleoprotein antibodies (RNP) are found in about 90% patients with Sjögren syndrome and are found in less than 5% of patients with other autoimmune diseases.
Hence, these anti-RNP antibodies, called SS-A and SS-B, are very good markers for this
disease.

Question 11

Which of the following blood studies is the best evidence of microvascular endothelial cell injury that typically occurs in systemic sclerosis (scleroderma)?

A. Hyperbilirubinemia
B. Hypoalbuminemia
C. Increased levels of von Willebrand factor
D. Increased levels of IgG
E. Increased levels of fibrinogen

Answer 11

C

Von Willebrand factor is produced and stored in endothelial cells. An endothelial cell
injury leads to elevated levels of this factor in blood.

Question 12

**Antibodies to centromeres are found in patients who have:**
A. systemic sclerosis
B. CREST syndrome
C. Sjogren syndrome
D. Polymyositis
E. dermatomyositis

Answer 12

B

Almost all patients who have anti-centromere antibodies have a form of scleroderma
called CREST. Symptoms of CREST syndrome, a limited form of scleroderma, are
calcinosis, Raynaud syndrome, esophageal dysmotility, sclerodactyly, and telangiectasis.
In contrast to CREST syndrome, systemic sclerosis is characterized by the appearance of
antibodies to DNA topoisomerase

Question 13

A 10 y/o girl presented with iliac or heliotrope discoloration of the upper eyelids, muscle weakness, and dusky red patches over the knuckles, elbows, and knees. Which antibody was more likely found in this patient’s blood?

A. Anti-histidyl-RNA synthetase
B. Anti-double-stranded DNA
C. Anti-single-stranded DNA
D. Anti-topoisomerase
E. Anti-ribonucleoprotein antibody

Answer 13

A

This girl most likely has dermatomyositis. The antibody most commonly found in inflammatory myopathies is directed against the histidyl-t-RNA.

Question 14

Mutations of the gene encoding the enzyme that is essential to the maturation of pre-B cells to mature B lymphocytes is the cause of

A. common variable immunodeficiency (CVID)
B. isolated IgA deficiency
C. DiGeorge syndrome
D. severe combined immunodeficiency
E. X linked agammaglobulinemia

Answer 14

E

X-linked agammaglobulinemia (Bruton agammaglobulinemia) is caused by the mutation
of Bruton tyrosine kinase (Btk), an enzyme essential for the maturation of pre-B cells into B lymphocytes. Because the defective B lymphocytes cannot produce immunoglobulins, there is agammaglobulinemia and reduced resistance to infections.

Question 15

Autoantibodies to IgA are found in approx. 40% of patients who have:

A. common variable immunodeficiency (CVID)
B. isolated IgA deficiency
C. DiGeorge syndrome
D. severe combined immunodeficiency
E. X linked agammaglobulinemia

Answer 15

B

Although they lack IgA in their blood and secretion, patients with congenital isolated IgA often have antibodies to IgA. Transfusion of blood to these patients may result in severe
anaphylactic reaction due to the reaction of the patient’s autoantibodies and the IgA in
the transfused blood.

Question 16

Which molecule on the surface of lymphocytes serves as the receptor for HIV?

A. CD3
B. CD4
C. CD8
D. CD15
E. CD20

Answer 16

B

CD4, the cell surface marker of T-helper lymphocytes, serves as a high affinity receptor
for the human immunodeficiency virus.

Question 17

In addition to T helper lymphocytes, which other cells serve as a major reservoir for HIV in lymph nodes?

A. B lymphocytes
B. pre B and pre T lymphocytes
C. cytotoxic T lymhocytes
D. follicular dendritic cells
E. plasma cells

Answer 17

D *verify this answer because prof said answer is B

The human immunodeficiency virus lives and replicates in CD4+ T-helper lymphocytes and follicular dendritic cells in the germinal centers of lymph nodes.

Question 18

The most common fungal pathogen infecting the mouth and the esophagus of patients with AIDS is

A. Candida albicans
B. cryptoccocus neolormans
C. Aspergillus fumigatus
D. Histoplasma capsulam
E. crytosporidium

Answer 18

A

In general, the most common fungal pathogens in patients with AIDS is Candida
albicans. Most often, it infects the mouth and the esophagus, but it can be found in many internal organs such as the vagina.

Question 19

Amyloid deposited in the tissue of patients who are on dialysis for chronic renal failure is most often biochemically related to which precursor protein?

A. light chain of IgG
B. SAA protein
C. Transthylein
D. B2 microglobulin
E. calcitonin

Answer 19

D

ß2-microglobulin is a component of the major histocompatibility complex on the cell
surface and is also normally present in deposits in the tissues of patients on long-term
hemodialysis, forming amyloid fibrils.

Question 20

Deposition of AL amyloid in the kidneys of patients with multiple myeloma usually results in:

A. acute renal failure
B. tubular necrosis
C. nephrotic syndrome
D. chronic pyelonephritis
E. nephrocalcinosis

Answer 20

C

Deposits of AL amyloid are typically found in the glomeruli, causing proteinuria.
Proteinuria is often severe, leading to a full blown nephrotic syndrome.