Determination of susceptibilities of 26 Leptospira sp. serovars to 24 antimicrobial agents by a broth microdilution technique.

The MICs of 24 antimicrobials for 26 Leptospira spp. serovars were determined using a broth microdilution technique. The MICs at which 90% of isolates tested were inhibited (MIC(90)s) of cefepime, imipenem-cilastatin, erythromycin, clarithromycin, and telithromycin were all </=0.01 microg/ml. The MIC(90)s of amoxicillin, aztreonam, cefdinir, chloramphenicol, and penicillin G were >/=3.13 microg/ml. Many antimicrobials have excellent in vitro activity against Leptospira.