大腸桿菌是各種感染症常見的致病菌，也是所有格蘭氏陰性菌中最常引起菌血症的細菌；然而，大腸桿菌卻很少引發心內膜炎。在此報告一位52歲女性病患無先前心臟病史，因為大腸桿菌泌尿道感染合併菌血症而住院。住院後理學檢查發現病患有明顯之心雜音且血液檢驗發現不明原因之貧血，故安排心臟超音波檢查，因而證實病患罹患三尖瓣心內膜炎。病患接受8周靜脈注射抗生素治療而痊癒出院。以此顯示，格蘭氏陰性菌如大腸桿菌所引發心內膜炎並不全然需要外科手術治療，較長時間靜注抗生素治療之內科保守性治療仍能治癒此嚴重之病症。

Despite being the most common gram-negative organism associated with bacteremia, Escherichiacoli remains an uncommon cause of infective endocarditis. Herein, a 52-year-old female without preexistingvalvular heart disease representing with E. coli urosepsis associated with unexplained heartmurmur and anemia, and therefore being proven of tricuspid valve endocarditis by transesophagealechocardiography, was reported. She survived after extended period of antimicrobial therapy. Surgery isprobably no longer to be mandatory in treating this serious infection.