First report of Bartonella quintana endocarditis in Japan.

Bartonella (Rochalimaea) species are increasingly recognized as a cause of endocarditis, but the total number of cases remains low. Especially, Bartonella quintana endocarditis is very rare and there have been no reports in Japan. A 66-year-old man was hospitalized because of dyspnea and fever. An echocardiogram showed severe mitral valve regurgitation, mild aortic valve regurgitation, and echogenic masses on the mitral and aortic valve. Six sets of blood cultures were negative. Replacement of the mitral- and aortic-valve with a mechanical valve was performed. However, due to symptomatic para-valvular leakage a re-mitral valve replacement was later performed. Unfortunately, the patient died 1 month after the operation owing to multiple organ failure. Four weeks after the second operation, blood culture yielded a Gram-negative bacillus. DNA was extracted from the colony and subjected to polymerase chain reaction amplification. Nucleotide sequence analysis (1,500 nucleotide positions) and a BLAST search of the EMBL/GENBANK database revealed 99.9% homology with the Bartonella quintana 16S rRNA gene. This is the first report of Bartonella quintana endocarditis in Japan, and should be considered with the view of culture negative endocarditis.