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What is McCallum's patch is diagnostic of : and explain in detail?
Answer is B (Rheumatic endocarditis) Mac Callum's Patch is a fi'ature of mural endocarditis in Rheumatic fever. Mac Callum's Patch 'Mc.Callum's patch' is the region of endocardial surface in the posterior walldeg of left atrium just above the posterior leaflet of mitral valve. It appears as a 'map like' area of thickened, roughened, and wrinkled pa of endocardium. It is perhaps produced as a result of regurgitant jets.