We used real-time PCR to detect Bartonella henselae DNA in 7.9% (5/63) of blood specimens from seronegative patients in Japan suspected of having cat-scratch disease. The combined use of serologic tests and real-time PCR to analyze blood specimens is recommended for the prompt, noninvasive laboratory diagnosis of cat-scratch disease.
Keywords: Bartonella henselae; Cat-scratch disease; Japan; bacteria; indirect fluorescence antibody assay; peripheral blood; real-time PCR; zoonoses.