Bartonella DNA PCR is a highly specific and sensitive method to detect the presence of Bartonella species DNA in clinical specimens. This assay can differentiate between Bartonella henselae and Bartonella quintana. The diagnosis of Bartonella infection should not rely solely on the result of a PCR assay. A negative PCR result indicates only the absence of Bartonella species DNA in the sample tested and does not exclude the diagnosis of the disease. Patients with a positive PCR result should be evaluated with other tests to further establish the diagnosis of the disease. A positive result should be considered in conjunction with clinical presentation and additional established clinical tests.