Etiologic agents and drug sensitivity in urinary tract infections: a survey of 786 urine cultures

ABSTRACT

In this survey, 786 urine cultures were studied retrospectively at Shaheed Dr. Rahnamoon Hospital in Tehran.the study showed that E. coli is the most common causative agent of urinary tract infections in both sexes, being responsible for 72% of all cases. Other etiologic microorganisms, in order of frequency, were Staphylococcus, Proteus, Klebsiella, Enterobacter and Diphteroids. Approximately 9% of all causative microorganisms were partially or totally resistant to the antimicrobials used in the antibiograms and practically all were among the nosocomial infections. The sensitivity resistance ratio of the etiologic agents in this study revealed that E.coli was most sensitive to amikacin,nitrofurantoin and nalidixic acid. However,it was resistant to ampicillin in 90% of all cases [compared to only 30% resistance rate in the western countries], which is probably due to inappropriate use of antibiotics in our country. We therefore conclude that the administration of ampicillin and co-trimoxazole, the two antimicrobials frequently used as an impirical therapy for urinary tract infections, is not appropriate