title: Incidence of antibiotic resistance and transmissible R factors in the gram-negative bowel flora of hospital patients on admission.
abstract: Stool specimens obtained on admission of 95 patients to a male urological ward were examined quantitatively for antibiotic-resistant gram-negative aerobic bacteria. All patients excreted resistant strains of some kind; 67% resistant Escherichia coli strains. Organisms resistant to sulphonamides, tetracyclines, and streptomycin occurred at a frequency of 10(-3)-10(-4). Ampicillin resistance was encountered most frequently, i.e. greater than 10(-2), whereas organisms resistant to chloramphenicol were found less often (10(-6)). Transmissible R factors were demonstrated in 53/121 (44%) resistant E. coli strains. A connection between tetracycline resistance and ability to transfer resistance was demonstrated. Resistance to chloramphenicol did not occur as a single resistance trait but was transferred from all strains resistant to this antibiotic.
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002701:Chloramphenicol / Q000494:pharmacology; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000302:isolation & purification; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification; D005111:Extrachromosomal Inheritance; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D008297:Male; D010403:Penicillin Resistance; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000302:isolation & purification; D011815:R Factors; D013307:Streptomycin / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D013449:Sulfonamides; D002701:Chloramphenicol; D000667:Ampicillin; D013752:Tetracycline; D013307:Streptomycin