This report describes the results of six antimicrobial regimens used for the treatment of brucellosis in an open, randomized study performed over two periods (1980-1983 and 1984-1987). In the first period, rifampicin and doxycycline were used for 4 weeks, trimethoprim-sulfamethoxazole for 6 months, and doxycycline for 6 weeks. During the second period, we used streptomycin for 2 or 3 weeks together with doxycycline for 6 weeks and rifampicin with doxycycline for 6 weeks. Comparison of the results showed the following: (1) no statistically significant findings were revealed when the different regimens were compared and (2) the regimens containing streptomycin yielded statistically more favorable results than those consisting of rifampicin and monotherapy when the patients treated with rifampicin were compared with those taking streptomycin and those receiving single-agent therapy. No significant differences were observed between monotherapeutic regimens and those including rifampicin.

No abstract

Chronic hepatosplenic suppurative brucellosis (CHSB) is a local reactivation of a previous brucellosis, coursing with an immunoglobulin G (IgG) and IgA secondary immunological response. The observation of two cases of CHSB with an apparent IgM response gave rise to a detailed serological study of three of our patients. We studied the first sample from all three patients and successive samples from two of them. In cases 1 and 2, we found samples with positive IgM lateral flow and IgM enzyme-linked immunosorbent assay results concomitantly with rheumatoid factor (RF); after absorption with anti-RF serum, these results were rendered negative. In patients 2 and 3 the diagnosis of brucellosis was delayed, because none of the test results were initially very significant. However, a clear seroconversion of IgG antibodies was observed in subsequent months; titers of the Brucellacapt and Coombs tests increased in similar ways, although Brucellacapt decreased more rapidly than Coombs, which persisted at high titers for years. In patient 3 a relapse was observed in the fourth year of follow-up, detected by Coombs and also by IgG lateral flow and counterimmunoelectrophoresis (CIEP), although not by the rose bengal, agglutination, or Brucellacapt tests. Serological changes in CHSB may sometimes be mild and are detected mainly by the Coombs test. Brucellacapt does not offer additional information, although IgG lateral flow and CIEP may be of some use. Careful surveillance of titer changes in the Coombs test is the best marker of infection activity. As the disease progresses, an intense IgG response may develop and RF sometimes appears, simulating an IgM response.