Advanced Pathology Mechanisms (Multi-topic) MCQs

Pathology · 12 free questions with answers & explanations.

1. In Duchenne muscular dystrophy, the absence of dystrophin leads to skeletal muscle fibre necrosis. The immediate consequence of dystrophin loss is:
2. Congo red staining with apple-green birefringence under polarised light is the gold-standard histochemical identification for amyloid. Which structural property of amyloid fibrils explains this birefringence?
3. A 6-year-old child has recurrent severe bacterial infections and has been hospitalised with Staphylococcus aureus lymphadenitis. Nitroblue tetrazolium (NBT) test is negative (no colour change). The diagnosis is:
4. The Philadelphia chromosome t(9;22)(q34;q11) results in a BCR-ABL1 fusion. The ABL1 portion contributes constitutive tyrosine kinase activity. Which domain of ABL1 is responsible for substrate phosphorylation?
5. A 55-year-old woman with Sjogren syndrome develops a monoclonal IgM kappa paraprotein. The risk of progression to a lymphoid malignancy is highest for which tumour?
6. In cholesterol cleft formation within atherosclerotic plaques, the liquefaction of the lipid core represents degradation of cholesterol esters by macrophage lipases. The histological appearance of cholesterol clefts after routine processing is:
7. Necroptosis is a regulated form of necrotic cell death requiring RIPK1, RIPK3, and MLKL. The final executioner step involves MLKL, which causes cell death by:
8. A renal biopsy from a patient with diabetic nephropathy shows nodular glomerulosclerosis (Kimmelstiel-Wilson lesion). The nodules are composed of:
9. A lymph node biopsy from a patient shows follicular hyperplasia with germinal centres containing tingible body macrophages. These macrophages appear starry against a dark background (starry sky pattern). The dark background cells are:
10. A patient with Gaucher disease type 1 has Gaucher cells on bone marrow biopsy. These cells represent lipid-laden macrophages engorged with glucocerebroside. The enzyme deficient in Gaucher disease is:
11. During the process of EMT (epithelial-to-mesenchymal transition) in cancer invasion, E-cadherin expression is silenced. Which transcription factors drive E-cadherin repression in EMT?
12. A patient develops reactive amyloidosis (AA type) after 20 years of rheumatoid arthritis. On biopsy, which site is MOST commonly sampled to detect systemic AA amyloidosis early?