Diseases

Question 1

What disease is characterized by a child that has to use both arms to push oneself up to stand? What are other features of the disease including inheritance and physical features?

Answer 1

Duchenne muscular dystrophy
Frame-shift mutation that is X-Linked
Person also has Pseudohypertrophy of the calves from fatty replacement of muscle
Tends to onset in early childhood and have a faster progression than Becker MD

Question 2

Types and differences between muscular dystrophies

Answer 2

There are two types of muscular dystrophy–Duchenne and Becker. They are different mutations of the same gene leading to atrophy of skeletal and cardiac muscle. Cardiomyopathy eventually develops leading to CHF and death. Both happen almost exclusively in males. X-linked

Duchenne: unset in early childhood and faster disease progression, live into 20s

Becker: onset later in adolescence, milder symptoms and slower progression, live into 40s

Question 3

Inheritance pattern for Hemophilia A & B

Answer 3

X-linked recessive

Question 4

Hemophilia A vs B

Answer 4

Hemophilia A: factor VIII deficiency

Hemophilia B: “Christmas Disease” factor IX deficiency

Both are X-linked recessive disorders and therefore affect primarily males

Question 5

Cystic Fibrosis:
Inheritance Pattern
Etiology
Organs affected

Answer 5

Autosomal Recessive
Gene mutations => dysfunctional CFTR protein that usually transports Cl ions
Affects mostly the lungs => chronic infections from thickened mucus
Also affects the pancreas => insufficiency => malabsorption, fatty stools, etc.
Causes male infertility by causing congenital malformation of the Vas Deferens
Also affects liver, kidney, intestines

Question 6

Hemochromatosis:

Answer 6

Any condition causing an accumulation of iron in the body

Usually a hereditary condition: autosomal recessive

Question 7

Marfan’s Syndrome:

Inheritance

Answer 7

Autosomal Dominant

Question 8

Neurofibromatosis:
Inheritance
Characteristic lesions

Answer 8

Autosomal Dominant

Cafe-au-Lait spots, neural tumors

Question 9

Fabry Disease:
Inheritance
Description

Answer 9

X-linked
Lysosomal storage disease
Enzyme deficiency causes accumulation of a glycolipid in vessels and organs causing altered function

Question 10

Rhabdomyoma

Answer 10

Benign tumor of striated muscle
Commonly in the heart–most common primary tumor of the heart in infants and children
Can also occur commonly in the tongue

Question 11

Crigler Najjar

Answer 11

UDP-glucuronyl transferase enzyme is absent
This is a necessary enzyme to conjugate bilirubin in the liver
Unconjugated hyperbilirubinemia

Question 12

Gilbert Syndrome

Answer 12

UDP-glucuronyl transferase enzyme is deficient or low
This is a necessary enzyme to conjugate bilirubin in the liver
Unconjugated hyperbilirubinemia

Question 13

Rotor Syndrome

Answer 13

Asymptomatic conjugated hyperbilirubinemia

Defective liver uptake and excretion of bilirubin pigments

Question 14

Dubin-Johnson Syndrome

Answer 14

Chronic conjugated hyperbilirubinemia

Defective canalicular protein causes impaired biliary excretion of bilirubin

Question 15

Describe Syphilis:
Causative agent
Progression of disease
Tests to diagnose

Answer 15

Agent: Treponema pallidum, spirochete

Disease: 3 stages:

• Primary: painless chancre on genitals
• Secondary: systemic, lesions on palms and soles and body, wart-like lesions on genitals ( condylomata lata)
• Tertiary: Gummas (chronic granulomas), neuro syphilis, prostitute’s pupil (accommodates, but doesn’t react to light)
• Congenital: transplacental after first trimester, rhagades (linear sores at corners of mouth), snuffles (nasal discharge), notched teeth, CN VIII deafness

Tests: FTA-ABS best test, VDRL/RPR are serological tests that are nonspecific, but can work

Question 16

What are the classic signs and symptoms of pancreatic adenocarcinoma?

Answer 16

Weight loss, epigastric pain radiating to the back, jaundice, elevated amylase and lipase and alk phos

Tumor markers for this cancer are CA 19-9 and carcinoembryonic antigen (CEA) (CEA less specific)

Tumor more commonly in pancreatic head, a very aggressive tumor that often has metastasized by the time it is diagnosed,

Patient may also have Trousseau’s Syndrome which is a migratory thrombophlebitis that will appear with swollen, red, tender limbs and then spontaneously resolve

Question 17

Trousseau Syndrome

Answer 17

Migratory thrombophlebitis
Presents with red, swollen limbs that are tender to palpation
Often associated with pancreatic adenocarcinoma

Question 18

Tay-Sachs Disease

Answer 18

Autosomal recessive disorder found commonly in Ashkenazi Jews and Pennsylvania Dutch and Louisiana Cajuns
Deficient hexosaminidase A enzyme prevents proper metabolism of sphingolipids causing a buildup of these lipids in neural tissue leading to progressive deterioration of nerve cells leading to decreasing mental and physical abilities.
The most common form begins at age 4-8 months and causes death by age 4
Characteristic sign is a cherry red spot on the macula of the retina
No hepatosplenomegaly is present
Lysosomes have onion skin

Question 19

Gaucher disease

Answer 19

Most common of the lysosomal diseases
Autosomal recessive
Lacks beta-glucocerebrosidase leading to accumulation of glucocerebroside
Symptoms include aseptic necrosis of the femur and HSM

Question 20

Fabry disease

Answer 20

X-linked recessive lysosomal storage disease
Lacks alpha-galactosidase A enzyme causing accumulation of ceramide trihexoside
Presents with peripheral neuropathy, cardiovascular and renal disease

Question 21

Niemann-Pick disease

Answer 21

Autosomal recessive disease
Lack sphingomyelinase
Progressive neurodegeneration and cherry red spot on macula
Hepatosplenomegaly and foam cells

Question 22

Thrombotic Thrombocytopenic Purpura (TTP)

Answer 22

Classic Sx remembered by FAT RN:
Fever
Anemia (microangiopathic) having schistocytes in blood smear
Thrombocytopenia
Renal failure
Neurologic disturbances

Caused by an antibody against ADAMTS13 which is a metalloprotease responsible for cleaving vWF multimers into smaller pieces. Accumulation of these multimers leads to platelet microaggregates which block small blood vessels throughout body.
Treatment by plasma exchange to remove the antibody

Question 23

Schizophrenia

Answer 23

Etiology: Increased Dopamine levels in the brain
SSx: Auditory hallucinations, grandiose delusions, disorganized speech with loose associations, catatonic behavior, disorganized behavior (these are the positive symptoms)
Negative Sx: 5 A’s–Flat affect, Avolition, Alogia, Anhedonia, poor Attention
Decreased dopamine in the prefrontal cortex may cause the negative Sx and may explain why antipsychotic meds don’t relieve these Sx.

Question 24

What are the effects of increased or decreased serotonin in the brain?

Answer 24

Increased serotonin can lead to aggression

Decreased serotonin can lead to depression

Question 25

What neurotransmitter levels are off in Parkinson’s disease?

Answer 25

Low dopamine levels

Question 26

Acromegaly

Answer 26

Caused by a pituitary adenoma that produces too much GH.
Patient will see a gradual increase in size of hands and feet, coarsening of features, large tongue, deepening of furrows, deepening of voice
Diagnosis is by measuring levels of IGF-1, and doing a glucose tolerance test to see if GH levels decrease with a glucose load.
Preferred treatment is surgery. Octreotide can be used in the meantime. It acts like somatostatin to counter the actions of GH.

Question 27

Addison Disease

Answer 27

Condition of steroid deficiency
SSx: hypotension, fatigue, skin hyperpigmentation
Treatment: glucocorticoid and mineralcorticoid replacement as necessary

Question 28

Syndrome of inappropriate ADH secretion

Answer 28

Occurs in head trauma or lung small cell cancer

Causes excess water resorption

Question 29

5 alpha-reductase deficiency

Answer 29

These individuals are genetically male, but have ambiguous genitalia at birth and are raised as females until puberty when an increase in testosterone will suddenly cause the growth of a penis.
Enzyme is needed to convert testosterone to DHT