Infective endocarditis with left to right intracardiac fistula due to Streptococcus anginosus - a rare complication caused by an even rarer bacterium

摘要

Although infective endocarditis (IE) has been described in reports datingfrom the Renaissance, the diagnosis still challenges and the outcome oftensurprises. In the course of time, diagnostic criteria have been updated andvalidated to reduce misdiagnosis. Some risk factors and epidemiology haveshown dynamic changes since degenerative valvular disease became morepredominant in developed countries, and the mean age of the affectedpopulation increased. Despite streptococci have been being well known asetiologic agents, some groups, although rare, have been increasingly reported(e.g., Streptococcus milleri.) Intracardiac complications of IE are common andhave a worse prognosis, frequently requiring surgical treatment. We report acase of a middle-aged diabetic man who presented with prolonged fever, weightloss, and ultimately severe dyspnea. IE was diagnosed based on a new valvularregurgitation murmur, a positive blood culture for Streptococcus anginosus, anechocardiographic finding of an aortic valve vegetation, fever, and pulmonarythromboembolism. Despite an appropriate antibiotic regimen, the patient died.Autopsy findings showed vegetation attached to a bicuspid aortic valve with anassociated septal abscess and left ventricle and aortic root fistula connectingwith the pulmonary artery. A large thrombus was adherent to the pulmonaryartery trunk and a pulmonary septic thromboemboli were also identified.