An Epidemiological Study on the Prevalence and Antibiotic Resistance Patterns of Bacteria Isolated from Urinary Tract Infections in Central Iran

Urinary tract infection (UTI) is one of the most common bacterial diseases in outpatients and inpatients worldwide. Treatment of UTI has become challenging due to the emergence of pathogens with increasing resistance to antimicrobial agents.
The aim of this study was to determine the prevalence and antimicrobial resistance patterns of main bacteria responsible for UTI.
In this study, 326 patients with UTI, referring to Shahid Motahari hospital of Fuladshahr, Iran, were evaluated between March 2015 and February 2016. The isolated bacteria were identified by biochemical tests. Disk diffusion method was applied to determine the antibiotic sensitivity of bacterial agents.
In a total of 326 positive urine cultures, 273 (83.74%) and 53 (16.25%) samples belonged to females and males, respectively. The most prevalent isolates were Escherichia coli (58.28%), Klebsiella spp. (11.65%), Staphylococcus spp. (11.65%), Enterobacter spp. (7.05%), Streptococcus spp. (3.68%), Enterococcus spp. (2.45%), Proteus spp. (1.22%), Pseudomonas spp. (0.61%), and Citrobacter spp. (0.61%), respectively. The antimicrobial susceptibility analysis of E. coli, as the predominant cause of UTI, revealed the following gentamicin (28.6%), ciprofloxacin (48.4%), nitrofurantoin (12.2%), nalidixic acid (63.7%), trimethoprim/sulfamethoxazole (67.9%), cephalothin (60%), cefotaxime (44.8%), imipenem (9.5%), amikacin (66.7%), and ampicillin (85.3%).
According to the present survey, E. coli isolates were the predominant pathogens in UTIs and were more prevalent in women than men. In the present study, the frequency of UTI pathogens was comparable to that reported in previous studies, showing an increasing resistance pattern to commonly prescribed antibiotics.