This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jones, C. H. Articles by Bradford, P. A. Search for Related Content PubMed PubMed Citation Articles by Jones, C. H. Articles by Bradford, P. A.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, February 2006, p. 505-510, Vol. 50, No. 2
0066-4804/06/$08.00+0     doi:10.1128/AAC.50.2.505-510.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Diagnostic PCR Analysis of the Occurrence of Methicillin and Tetracycline Resistance Genes among Staphylococcus aureus Isolates from Phase 3 Clinical Trials of Tigecycline for Complicated Skin and Skin Structure Infections

Infectious Diseases Discovery Research, Wyeth Research, Pearl River, New York

Received 3 October 2005/ Returned for modification 27 October 2005/ Accepted 3 November 2005

Diagnostic PCR assays were developed to track common genetic determinants of oxacillin resistance as well as resistance to classical tetracyclines in Staphylococcus aureus isolates from the recently completed worldwide phase 3 clinical trials of tigecycline. A total of 503 unique S. aureus strains isolated from complicated skin and skin structure infections were analyzed. The mecA gene was amplified from 120 strains (23.9%) determined to be resistant to oxacillin (MICs 4 µg/ml). The prevalence of the mecA gene was found to vary regionally from 6.5% to 50.9% among isolates originating in Eastern Europe and North America, respectively. The presence of a tetracycline resistance determinant, tet(M) or tet(K), among methicillin-resistant S. aureus (MRSA) isolates also varied regionally, with a range of 11.9% to 46.2% among isolates tested from North America and Eastern Europe, respectively. The occurrence of a tetracycline resistance marker in methicillin-susceptible S. aureus (MSSA) strains varied from 2.5 to 16.1% among the isolates tested across the regions of study. The presence of tet(M) or tet(K) had no discernible effect on the tigecycline MICs for either MRSA or MSSA strains, which is consistent with the ability of the glycylcyclines to retain activity in the presence of both the ribosomal protection and efflux mechanisms of resistance to the tetracyclines.

This article has been cited by other articles:

• Tuckman, M., Petersen, P. J., Howe, A. Y. M., Orlowski, M., Mullen, S., Chan, K., Bradford, P. A., Jones, C. H. (2007). Occurrence of Tetracycline Resistance Genes among Escherichia coli Isolates from the Phase 3 Clinical Trials for Tigecycline. Antimicrob. Agents Chemother. 51: 3205-3211 [Abstract] [Full Text]  
• Bolmstrom, A., Karlsson, A., Engelhardt, A., Ho, P., Petersen, P. J., Bradford, P. A., Jones, C. H. (2007). Validation and Reproducibility Assessment of Tigecycline MIC Determinations by Etest. J. Clin. Microbiol. 45: 2474-2479 [Abstract] [Full Text]