USE OF BARTONELLA ANTIGENS FOR SEROLOGIC DIAGNOSIS OF CAT-SCRATCH DISEASE AT A NATIONAL REFERRAL CENTER

Background: Bartonella henselae (formerly the genus Rochalimaea) has r ecently been isolated from patients with cat-scratch disease and their cats, and since September 1992 the Centers for Disease Control and Pr evention has offered an indirect fluorescent antibody assay for Barton ella-specific antibody. Methods: Physicians submitted serum samples fr om patients suspected of having cat-scratch disease or other Bartonell a-associated illness and completed a questionnaire that recorded clini cal information. Indirect fluorescent antibody assay was performed wit h the use of antigen derived from three Bartonella species: B henselae , Bartonella quintana, and Bartonella elizabethae. Results: During 16 months, 3088 serum samples were received. The largest numbers of speci mens and the highest percentages positive (titer, greater than or equa l to 64) were observed in the fall and winter. Clinical histories of t he first 600 patients for whom serum samples and completed information forms were received were examined in detail; seropositivity was signi ficantly associated with cat contact, cat age of less than 1 year, cat scratch, presence of an inoculation papule, and regional adenopathy. Of 91 patients whose illness met a strict clinical definition of cat-s cratch disease, 86 (95%) had titers of 64 or greater to either B hense lae or B quintana. A fourfold rise or fall in titer was observed in 87 of 132 patients with paired serum samples. Conclusions: The indirect fluorescent antibody assay for Bartonella-specific antibody is sensiti ve for the diagnosis of cat-scratch disease. Redefinition of cat-scrat ch disease on the basis of cause and use of this assay as a diagnostic criterion is recommended.