A 65-year-old woman who had previously undergone aortic root replacement with a bioprosthetic valve (Bentall operation) in treatment of annuloaortic ectasia became feverish after developing dental caries and was admitted to our hospital. Transesophageal echocardiography showed an 18 × 4-mm vegetation on her prosthetic valve. Campylobacter fetus was isolated on blood cultures, and she was diagnosed with infectious endocarditis. Aggressive combined antibiotic treatment was effective for her recovery. C. fetus infection is a rarely reported cause of prosthetic valve endocarditis.
