STRATEGY TO DETECT AND IDENTIFY BARTONELLA SPECIES IN ROUTINE CLINICAL LABORATORY YIELDS BARTONELLA-HENSELAE FROM HUMAN IMMUNODEFICIENCY VIRUS-POSITIVE PATIENT AND UNIQUE BARTONELLA STRAIN FROM HIS CAT

We wished to develop a cost-effective, rapid strategy to detect and id entify Bartonella species in the clinical laboratory and to determine the prevalence of Bartonella infection in the Houston veteran populati on. Bartonella colonies were identified by colony morphology, Gram sta in, RapID ANA, repetitive extragenic palindromic-PCR (REP-PCR) and who le-cell fatty acid (CFA) analysis, and these methods were compared for their usefulness. A new test order for ''Rochalimaea culture'' (the g enus Bartonella was previously known as the genus Rochalimaea) was ins tituted, and in addition, all blood specimens submitted for fungal cul ture (obtained in an isolator tube) were processed for Bartonella cult ure. Over a 16-month period we isolated Bartonella henselae from only 0.4% (2 of 533) of total cultures but from 1% (2 of 204) of human immu nodeficiency virus-positive patients. After sufficient growth, identif ication of the Bartonella isolates to the species level could be obtai ned in 2 days. The REP-PCR allowed discrimination of all known species , whereas CFA analysis distinguished all except B. henselae and Barton ella quintana. The RapID ANA results failed to differentiate between B . henselae and B. quintana, and results for other species differed by only one or two tests. Blood obtained from a kitten which had been int roduced into the household of one patient 2 months before the onset of fever yielded a Bartonella strain which was shown to be different fro m the strain from the patient and distinct from other Bartonella speci es by a combination of REP-PCR, CFA, and growth characteristics. Subse quent analysis of the citrate synthase gene sequence showed only an 86 % similarity with any of the other known Bartonella species, suggestin g that this isolate represents a distinct, previously uncharacterized species of Bartonella.