Failure of ceftriaxone in the treatment of acute brucellosis.

In an open, multicenter study conducted in Israel in 1989, 18 patients with acute brucellosis were randomized to receive either less than or equal to 2 g of intramuscularly administered ceftriaxone daily for at least 2 weeks or doxycycline for 4 weeks plus streptomycin for 2 weeks. All 10 patients treated with the combination of doxycycline plus streptomycin responded promptly, and their infections did not relapse during 6 months of follow-up. Of eight patients treated with ceftriaxone, six did not respond initially; when ceftriaxone was replaced by the combination of doxycycline and streptomycin, patients responded immediately. No relapses of infection were observed in these patients during follow-up. One patient who received ceftriaxone responded and remained well at the end of 6 months of follow-up, and one patient who initially responded to therapy with this drug experienced relapse of infection within 3 weeks but recovered when the doxycycline/streptomycin regimen was initiated. We conclude that despite encouraging data from in vitro studies and promising clinical studies, 2 g of ceftriaxone administered im daily should not be considered appropriate therapy for brucellosis.