Effect of trimethoprim on the occurrence of drug-resistant coliform bacteria in the faecal flora.
The occurrence of drug-resistant coliform bacteria was studied in the faecal flora of 30 persons receiving for 3 weeks either trimethoprim alone, a combination of sulphamethoxazole and trimethoprim, or a combination of sulphamethoxydiazine and sulphamethoxazole. Bacterial sensitivity was tested against trimethoprim, sulphamethoxazole-trimethoprim, sulphamethoxazole, and sulphaisodimidine. After treatment with trimethoprim alone, no increase in the occurrence of strains resistant to either trimethoprim or sulphonamides was observed. After treatment with sulphamethoxazole-trimethoprim, the faecal flora contained an increased percentage of sulphonamide-resistant coliforms but significantly less than found after treatment with sulphamethoxydiazine-sulphamethoxazole. In the persons receiving the sulphonamides only, a rapid increase in sulphonamide-resistant coliforms was observed. During the whole study, only one trimethoprim-resistant coliform strain was detected.
D000293:Adolescent; D000328:Adult; D004338:Drug Combinations; D004352:Drug Resistance, Microbial; D004755:Enterobacteriaceae / Q000187:drug effects*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D008875:Middle Aged; D013417:Sulfameter / Q000494:pharmacology*; D013420:Sulfamethoxazole / Q000494:pharmacology*; D013424:Sulfanilamides / Q000494:pharmacology*; D014295:Trimethoprim / Q000494:pharmacology*
D004338:Drug Combinations; D013424:Sulfanilamides; D013417:Sulfameter; D014295:Trimethoprim; D013420:Sulfamethoxazole