Epidemiology of pathogens causing urinary tract infections in an urban community in southern Brazil.

The frequency of urinary tract infection (UTI) and uropathogens in the community was determined by assessing urine culture results of outpatients at a Brazilian public laboratory in a year period. Patients were classified according to sex and age; women were additionally classified considering pregnancy or diabetes. Cultures were considered positive when growing pure cultures with colony counts >10CFU/mL. Of the 64,562 urine cultures performed 11,122 (17.2%) turned out positive. UTI was significantly more common among women; however, its frequency varied among patient subgroups. The most common uropathogens were Escherichia coli (54.7%), Streptococcus agalactiae (18.8%), and Proteus mirabilis (5.6%). E. coli frequency was higher among women; even though pregnant women showed a lower incidence (41.1%), similar to that observed in adult men (40.9%). S. agalactiae was the second most commonly isolated species among women, with a higher incidence among pregnant women (31.2%). In contrast, P. mirabilis was the most common species recovered from boys (32%). These data indicate that the distribution of uropathogens varies among groups of patients suggesting that host characteristics may be associated with greater susceptibility to specific uropathogens.