A 50-year-old alcoholic man with a 1-year history of pyrexia of unknown origin was admitted with symptoms of endocarditis. Large vegetations on his mitral and aortic valve were found on echocardiography. Using the Bactec 9240 system. Bartonella quintana could be grown from two culture sets of blood collected before the start of antimicrobial therapy. This is the first case report of culture-proven bartonella infection in the UK. and is noteworthy because Bartonella quintana was detected in conventional blood culture systems after prolonged incubation.