Transferable antibiotic resistance in enterobacteriaceae isolated from urinary tract infections in general practice.

138 different coliform isolates from patients with UTI in 2 General Practices in Stockport, England, showed an incidence of drug resistance of 36%: 47% of these strains transferred resistance to E. coli K12. Multiple resistance, i.e. resistance to more than 2 drugs occurred in more than a quarter of resistant isolates and sulphonamide resistance was most common. More than twice as many strains in this series (1973--74) were sulphonamide resistant compared with a previous survey (1968--70). MIC values of R+ resistant isolates were much higher with sulphonamide resistant strains than the probable urine levels during therapy, but the situation with ampicillin and tetracycline levels was variable.