Serological responses to brucellosis in HIV-seropositive patients

Serial sera from 2 patients infected with the human immunodeficiency virus (HIV) type 1 attending a clinic in Nairobi, Kenya, and with blood cultures yielding Brucella melitensis, were tested by enzyme-linked immunosorbent assay for their serological response (Brucella-specific immunoglobulin (Ig) M and IgG) to Brucella infection. Antibody responses were comparable to those of immunocompetent individuals, one patient showing serology typical of acute brucellosis, the other of chronic brucellosis. Sera from 100 other patients, 65 of whom were HIV-positive, attending the same clinic but whose routine microbiological cultures were negative for Brucella, were tested retrospectively for Brucella-specific antibody. Eight had Brucella-specific IgM and IgG, 6 had IgM only and 21 had IgG only, suggesting relatively high levels of exposure to Brucella in the study cohort. There was no association between Brucella antibody status and HIV status. Brucellosis is probably underdiagnosed in Kenya. Brucella serology may be helpful in the diagnosis of patients with non-specific symptoms in East Africa, regardless of HIV status.