Antibiotic resistance of urinary pathogens isolated from patients attending the Toronto Hospital between 1986 and 1990.

A study was carried out on 1523 urinary isolates obtained at The Toronto Hospital, Canada's largest tertiary care establishment, over three 1-month periods in 1986, 1987 and 1990. Escherichia coli was the most frequently isolated organism, with Enterococcus spp. the second most common isolate in 1986 and 1987, and Streptococcus spp. in 1990. Pseudomonas aeruginosa isolates were found to be resistant to many of the antimicrobial agents tested. Resistance patterns were found to commonly prescribed ampicillin, co-trimoxazole and, to some extent, the new fluoroquinolones, ciprofloxacin and norfloxacin. These results are relevant to the treatment and management of urinary tract infections in patients attending a tertiary care hospital.