An autopsy case of infective endocarditis showing multiple cerebral infarctions caused by bacterial embolization from vegetation in a chronic hemodialysis patient

Abstract

Key words：infective endocarditis, multiple cerebral infarctions, enbolism, hemodialysis, MRSA 〈Abstract〉 A 65-year-old man who had undergone hemodialysis for chronic renal failure due to diabetes mellitus since 1997 was admitted to the Department of Dermatology for cellulitis on the right lower extremity on April 12, 2010. He had a history of diabetic gangrene and had been treated in the dermatology department since 2007. On his 2nd hospital day, he suddenly showed loss of consciousness. Magnetic resonance imaging diffusion-weighted images (MRI-DWI)revealed fresh multiple cerebral infarctions. An echocardiogram revealed mitral valve vegetation and blood culture grew gram-positive coccus bacteria, confirming the diagnosis of infective endocarditis. On the 5th day, he died of systemic sepsis and multiple organ failure. Subsequently, gram-positive coccus was detected as Methicillin-resistant Staphylococcus aureus(MRSA). At autopsy, the mitral valve showed vegetation of 2 cm in diameter and multiple embolizations in the brain, liver, and spleen. Bacterial culture of both the vegetation and emboli revealed the same bacteria as MRSA. This case is very valuable as we could prove that the multiple cerebral infarctions and systemic embolization in the liver and spleen were caused by the mitral valve vegetation of MRSA.