A case of native valve infective endocarditis caused by bacillus cereus

Bacillus cereus is a ubiquitous organism that often contaminates microbiological cultures but rarely causes serious infections in humans. It is the causative organism of infective endocarditis (IE), a disease typically associated with intravenous (IV) drug abusers. Thus, almost all reported cases have involved the tricuspid valve. We report a case of native mitral valve (MV) IE caused by B. cereus in a 54 year-oldman with moderate MV regurgitation but no apparent history of IV drug use. He presented with fever and dyspnea on exertion, symptoms which had been ongoing for 2 months. B. cereus infection was determined by blood culture examination. A transthoracic echocardiography revealed that mobile vegetations had attached to the MV. He was treated with IV antibiotics for a total of 6 weeks and received MV replacement surgery. He has maintained a good clinical recovery without complications since discharge.