Antimicrobial-Resistant Strains of Clostridium difficile from North America

Abstract

ABSTRACTA total of 316 toxigenicClostridium difficileclinical isolates of known PCR ribotypes from patients in North America were screened for resistance to clindamycin, metronidazole, moxifloxacin, and rifampin. Clindamycin resistance was observed among 16 different ribotypes, with ribotypes 017, 053, and 078 showing the highest proportions of resistance. All isolates were susceptible to metronidazole. Moxifloxacin resistance was present in >90% of PCR-ribotype 027 and 053 isolates but was less common among other ribotypes. Only 7.9% of theC. difficileisolates were resistant to rifampin. Multidrug resistance (clindamycin, moxifloxacin, and rifampin) was present in 27.5% of PCR-ribotype 027 strains but was rare in other ribotypes. These results suggest that antimicrobial resistance in North American isolates ofC. difficilevaries by strain type and parallels rates of resistance reported from Europe and the Far East.