Q- A 2-year-old child has recurrent infections with catalase-positive organisms. Neutrophils show absent oxidative burst on flow cytometry. Which enzyme is defective?
A- Adenosine deaminase
B- Glucose-6-phosphate dehydrogenase
C- NADPH oxidase
D- Myeloperoxidase
Q- A patient has difficulty rising from a chair and climbing stairs. Biopsy shows endomysial inflammation and CD8+ T-cell infiltration. Which condition is most likely?
A- Becker muscular dystrophy
B- Dermatomyositis
C- Polymyositis
D- Spinal muscular atrophy
Q- A 35-year-old woman has heat intolerance, weight loss, and palpitations. Lab: ↓TSH, ↑T3/T4. Which finding is most consistent with Graves disease?
A- Anti-thyroid peroxidase antibodies
B- Anti-TSH receptor antibodies
C- Decreased radioactive iodine uptake
D- Non-tender thyroid with fibrosis
Q- A patient has episodes of hematuria and hearing loss. Electron microscopy shows splitting of the glomerular basement membrane. Which collagen is defective?
A- Type I collagen
B- Type II collagen
C- Type III collagen
D- Type IV collagen
Q- A patient with peptic ulcer disease is treated with a drug that irreversibly inhibits the H+/K+ ATPase. Which drug was given?
A- Cimetidine
B- Omeprazole
C- Ranitidine
D- Sucralfate