Infective Endocarditis Caused by Streptococcus viridans in a Previously Healthy Man: A Case Report

Infective endocarditis (IE) is a rare and potentially fatal infection of the heart valves, often caused by streptococci, staphylococci, and enterococci. This case is particularly significant as it describes IE caused by Streptococcus viridans in a 36-year-old male patient, previously healthy with no known risk factors, who presented with a three-week history of fever, night sweats, and fatigue. Initially, the clinical presentation was attributed to an atypical infection due to his occupational exposure, and he was empirically treated with doxycycline, showing apparent clinical improvement. However, blood cultures were positive for Streptococcus viridans, leading to hospitalization and suspicion of endocarditis. Echocardiography revealed congenital aortic valvulopathy (bicuspid aortic valve) with moderate regurgitation but no evidence of vegetation. A transesophageal echocardiogram identified vegetations, confirming the diagnosis of IE. Treatment with ceftriaxone and gentamicin resulted in a favorable clinical response after four weeks. This case highlights the diagnostic challenges of IE in atypical presentations and the importance of considering IE in patients with fever and positive blood cultures, even in the absence of known cardiac disease or previous risk factors. It also emphasizes the need for timely diagnosis to prevent severe complications associated with endocarditis. The authors aim to underscore the indolent course of IE in this rare clinical presentation.