Endocardite com envolvimento multivalvar e hemoculturas negativas: um relato de caso

Abstract

This study reports the case of a 47-year-old female patient diagnosed with nonbacterial thrombotic endocarditis (NBTE) involving the mitral, aortic, and tricuspid valves. NBTE is a rare condition characterized by sterile vegetations composed of fibrin and platelets, typically associated with hypercoagulable states such as malignant neoplasms and autoimmune diseases. The patient was hospitalized after incidental detection of vegetations on echocardiography performed during the investigation of anemia. Evaluation included laboratory and microbiological tests with negative blood cultures and exclusion of infectious causes, as well as thorough screening for malignancies and autoimmune diseases, without identifying any underlying condition to explain the hypercoagulable state. Management was based on full anticoagulation and serial echocardiography demonstrating regression of vegetations after seven months. There were no clinical or radiological signs of embolization. This case underscores the importance of differential diagnosis in valvular vegetations with negative blood cultures, the need for comprehensive investigation of predisposing conditions, and the possibility of NBTE even in the absence of an identifiable underlying disease. It also highlights the need for rigorous medical follow-up to monitor valvular evolution, prevent complications, and enable early detection of occult prothrombotic states.