Antimicrobial susceptibilities of clinical Desulfovibrio isolates

The antimicrobial susceptibilities of 16 clinical isolates of Desulfovibrio spp. were determined. All or most isolates were susceptible to imipenem (MIC(90) [MIC at which 90% of the isolates tested were inhibited], 0.5 microg/ml), metronidazole (MIC(90), 0.25 microg/ml), clindamycin (MIC(90), 4 microg/ml), and chloramphenicol (MIC(90), 16 microg/ml) but were resistant or intermediate to penicillin G (MIC(90), 64 microg/ml), piperacillin (MIC(90), 256 microg/ml), piperacillin-tazobactam (MIC(90), 256 microg/ml), cefoxitin (MIC(90), >256 microg/ml), and cefotetan (MIC(90), 64 microg/ml). Among isolates with decreased susceptibility to beta-lactams (n = 15), only six were beta-lactamase positive and susceptible to amoxicillin-clavulanate and ticarcillin-clavulanate.