[Gemella endocarditis: an aggressive entity].

The authors present a rare case of subacute endocarditis caused by Gemella morbillorum. A 72-year-old man, with a history of hypertension, aortic valve disease and upper and lower endoscopy six months previously, was admitted due to fever and abdominal pain. He also complained of long-standing dyspnea on exertion and petechiae on his lower limbs. Imaging scans showed a consolidation in the lower left lung field, a splenic infarct and a left subphrenic abscess. Transthoracic echocardiogram findings were highly suggestive of endocarditis affecting three valves, with destruction of the mitral valve anterior leaflet. G. morbillorum was identified in three blood cultures and was considered the etiologic pathogen. Due to the patient's worsening condition, he underwent cardiac surgery, aiming to control the infection and to resolve the associated mechanical complications. This case highlights the need for a complete and thorough history to arrive at likely diagnostic hypotheses that, together with complementary exams, will lead to correct diagnosis and the prompt institution of appropriate therapy.