Abstract
Several studies have identified thymidine excess in susceptibility test media as the cause of spurious resistance of various bacteria to sulfamethoxazole-trimethoprim. We document the phenomenon in Salmonella typhi and Salmonella paratyphi-A and demonstrate its occurrence in 3 of 17 (18%) lots of Mueller-Hinton agars now in use in major medical laboratories in Lima, Peru. The findings are particularly significant because sulfamethoxazole-trimethoprim is an important alternative to chloramphenicol or ampicillin for the treatment of typhoid and paratyphoid fevers.
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Selected References
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- Crider S. R., Colby S. D. Susceptibility of enterococci to trimethoprim and trimethoprim-sulfamethoxazole. Antimicrob Agents Chemother. 1985 Jan;27(1):71–75. doi: 10.1128/aac.27.1.71. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Herzog C. H. Drug treatment of typhoid fever. Br Med J. 1976 Oct 16;2(6041):941–941. doi: 10.1136/bmj.2.6041.941-a. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Koch A. E., Burchall J. J. Reversal of the antimicrobial activity of trimethoprim by thymidine in commercially prepared media. Appl Microbiol. 1971 Nov;22(5):812–817. doi: 10.1128/am.22.5.812-817.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mukhtar E. D., Mekki M. O. Trimethoprim-sulphamethoxazole in the treatment of enteric fever in the Sudan. Trans R Soc Trop Med Hyg. 1981;75(6):771–773. doi: 10.1016/0035-9203(81)90407-7. [DOI] [PubMed] [Google Scholar]
- Rao R. S., Sundararaj T., Subramanian S., Shankar V., Murty S. A., Kapoor S. C. A study of drug resistance among Salmonella typhi and Salmonella paratyphi A in an endemic area, 1977-79. Trans R Soc Trop Med Hyg. 1981;75(1):21–24. doi: 10.1016/0035-9203(81)90008-0. [DOI] [PubMed] [Google Scholar]
- Vongsthongsri U., Tharavanij S. Susceptibility of Salmonella typhi to chloramphenicol, ampicillin and cotrimoxazole. Southeast Asian J Trop Med Public Health. 1980 Jun;11(2):256–261. [PubMed] [Google Scholar]