Rheumatic mitral stenosis results from recurrent streptococcal pharyngitis triggering an autoimmune response. The cardiac lesion in acute rheumatic fever—Aschoff bodies—consists of:
- A Non-caseating granulomas with Aschoff cells (activated macrophages with 'caterpillar' nuclei) and fibrinoid necrosis ✓
- B Caseating granulomas with giant cells in the myocardium
- C Microabscesses with neutrophil infiltrate in the interstitium
- D Amyloid deposits in the myocardial interstitium with giant cells
Correct answer: A. Non-caseating granulomas with Aschoff cells (activated macrophages with 'caterpillar' nuclei) and fibrinoid necrosis
Explanation
Aschoff bodies are pathognomonic cardiac lesions in rheumatic fever: foci of fibrinoid necrosis surrounded by Anitschkow cells (Aschoff cells)—activated macrophages with characteristic 'caterpillar' (owl-eye) nuclei—along with lymphocytes and occasional giant cells. They are non-caseating. Caseating granulomas are characteristic of tuberculosis; microabscesses suggest bacterial myocarditis; amyloid deposits occur in amyloid heart disease.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.