Analysis of serological cross-reaction between Chlamydiae and Bartonella henselae *
The diagnosis of Chlamydia trachomatis infection in many cases continues to rely on serology. However, serological cross-reaction between members of the genera Chlamydia and Bartonella have been documented. Sera from 7 of 15 patients with C.trachomatis infection and anti-C.psittaci rabbit serum reacted with B.henselae at titers ranging from 1 : 16 to 1 : 256. Absorption of these sera with B.henselae removed anti-B.henselae antibody from six patients, whereas absorption with C.trachomatis did not remove it from the scrum of a patient who was originally diagnosed as having C.trachomatis infection. The antibody titer to C.trachomatis in this patient's serum was thus false positive resulting from the cross-reaction between anti-B.henselae and C.trachomatis antigens. Immunoblot analysis indicated that seven patients' sera contained antibodies reactive with 40, 48 and 60kDa proteins in B.henselae organisms and that antibodies reactive with 48kDa protein in C.trachomatis organisms were contained in the serum of the patient with B.henselae infection. The results strongly suggest that serum absorption with B.henselae antigens prior to detection of the anti-C.trachomatis antibody is important in excluding the false positive results in the serodiagnosis. (Accepted on September 16, 1999) Kawasaki Igakkaishi 25(4) : 247-255, 1999
