[Etiological factors of community acquired urinary tract infections in hospitalized patients]

Etiological factors of community-acquired urinary tract infections (UTI) are specific for age, gender, season, complication of UTI and type of UTI. Their prevalence and susceptibility to antimicrobial agents shows geographic and time variability.

To evaluate etiological characteristics of acute community-acquired UTI in hospitalised patients.

This retrospective-prospective study included 200 adult patients with community-acquired UTI who were, in view of the serious clinical picture and unsuccessful ambulatory treatment, hospitalised in the Clinic for Infectious Diseases in Tuzla, for a period of two years (2006 and 2007). The data concerning the age, gender, season, complication of UTI and type of UTI were collected from the patient's records. Urine analysis was done following standard microbiological methods, and the antibiogram was done following standard disc-diffusion method on the Mueller-Hinton agar.

The dominant etiological factors of UTI were: E. coli (73.5%), Klebsiella spp. (8.5%), Proteus mirabilis (5.5%), Pseudomonas aeruginosa (4.5%) and Enterococcus faecalis (3%). The predominant etiological factor of this UTI was E. coli (P < 0.0001). E. coli was significantly more frequent etiological factor of UTI in females (P < 0.0001). There was no significant difference in the frequency between etiological factors of UTI for different age groups of patients (P = 0.173), or for different seasons (P > 0.05). All etiological factors are significantly more frequent during warmer periods of the year (P < 0.05). E. coli is a significantly more frequent etiological factor in complicated and non-complicated pyelonephrytis and cystourethritis (P < 0.05), but there was no significant difference of frequency between etiological factors of prostatitis (P = 0.7163). By analyzing the susceptibility for antimicrobials, we found that E. coli has good susceptibility for Cephalosporins of the third generation, for Gentamycin, Nitrofurantoin, Norfloxacin, Ciprofloxacin and Pipemidin acid (susceptibility higher than 88.7%), Klebsiella spp. for Imipenem and Meropenem (susceptibility 100%), Proteus mirabilis for Imipenem (susceptibility 100%) and relatively for Amikacin (susceptibility 81.8%), Pseudomonas aeruginosa for Imipenem (susceptibility 100%) and for Meropenem (susceptibility 87.5%) and Enterococcus faecalis for Vancomycin (susceptibility 100%) and relatively for Ampicillin, Amoxicillin, Ciprofloxacin, Doxicyclin and Nitrofurantoin (susceptibility 83.4%).

Etiological characteristics of UTI are specific for different regions. Evaluation of these characteristics in our region is the basis for empirical antimicrobial therapy of UTI, which is necessary for a timely and successful treatment of UTI.