CHANGING TRENDS IN FREQUENCY AND ANTIMICROBIAL RESISTANCE OF URINARY PATHOGENS IN OUTPATIENT CLINICS AND A HOSPITAL IN SOUTHERN ISRAEL, 1991-1995

In order to monitor changes in the frequency and antimicrobial resista nce of urinary pathogens over several years, urinary cultures received from outpatient clinics and from a hospital during a period of one mo nth each in 1991 and 1995 were analyzed at a clinical microbiology lab oratory, In 1991 and 1995, 1366 and 1534 significant monomicrobic cult ures respectively were reviewed. The frequency of Escherichia coli dro pped significantly in the outpatient clinics from 70.5% to 61.2% (p < 0.0001). The frequency of Proteus mirabilis, Morganella morganii, Pseu domonas aeruginosa and other gram-negative bacteria also decreased, bu t the frequency of Klebsiella sop, and Enterobacter spp. increased fro m 2.6% to 5.8% (p < 0.0001). In the hospital, the frequency of Enterob acter spp. (p < 0.04), Escherichia coli and Morganella morgianii decli ned from 1991 to 1995, whereas the frequency of Pseudomonas aeruginosa (p = 0.001), Acinetobacter spp. (p < 0.05), Klebsiella spp., Proteus mirabilis and other gram-negative rods increased considerably, The fre quency of gram-positive aerobic bacteria rose markedly in outpatient s pecimens from 6.1% to 13.5% (p < 0.0001), while a decline from 14.4% t o 9.3% was noted in hospital specimens (p < 0.02). A significant rise in the resistance of Escherichia coli to gentamicin and ciprofloxacin (p < 0.0001) was detected in outpatient isolates. In the hospital, gra m-negative urinary pathogens demonstrated increased resistance to ampi cillin (p = 0.042), cefuroxime (p = 0.005), gentamicin (p = 0.002) and ciprofloxacin (p < 0.0001) during the study period. The changing etio logy of urinary tract infections and the increasing resistance of orga nisms indicate that periodic monitoring and possibly also modification of empirical therapy are required.