PELAEZ T, PEREZ C, ALCALA L, CUEVAS O, MUNOZ P, RODRIGUEZ-CREIXEMS M, BOUZA E; Interscience Conference on Antimicrobial Agents and Chemotherapy (41st : 2001 : Chicago, Ill.).
Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 2001 Dec 16-19; 41: abstract no. E-2270.
Hospital Gregorio Maranon, Madrid, Spain
BACKGROUND: Resistance to metronidazole and vancomycin of clinical isolates of toxigenic C. difficile has been well demonstrated by us and by other groups. Barbut et al. (AAC 1999, pp 2607-2611) suggested that decreased susceptibility to metronidazole could be associated with non-toxigenic C. difficile strains. Our aim was to compare the incidence of metronidazole and vancomycin resistance in a large sample of toxigenic and non-toxigenic C. difficile clinical isolates. METHODS: From 1992 to 2001, our laboratory recovered 2499 clinical isolates of C. difficile. Of these, 2,328 were toxigenic (93.1%) and171 were non-toxigenic (6.9%). We performed the antimicrobial susceptibility testing of 420 toxigenic and 57 non-toxigenic CD isolates, available for study. Antimicrobial susceptibility testing was performed according to the NCCLS recommendations for anaerobic bacteria. The concentrations were: metronidazole (0.125- 32 microg/ml) and vancomycin (0.125-32 microg/ml). RESULTS: The MIC[50]/MIC[90] values (microg/ml) of toxigenic and non-toxigenic CD isolates were, respectively, 0.5/2 and 2/16 against metronidazole, and1/2 and 2/2 against vancomycin. For both groups, percentages of resistance were 2.3 and 10.5% (p0.05) against metronidazole, and2.3 and 5.2 metronidazole, and 2.3 and 5.2% against vancomycin (p=NS). CONCLUSIONS: Metronidazole and vancomycin resistance is more than anecdotal in our clinical population. The reasons for a higher incidence resistance to metronidazole in non-toxigenic strains are not clear to us at present.
Publication Types:
Keywords:
- Metronidazole
- Microbial Sensitivity Tests
- Vancomycin
Other ID:
UI: 102269457
From Meeting Abstracts