Antimicrobial resistance in patients with urinary tract infections and the impact on empiric therapy in Serbia.

INTRODUCTION: Surveillance of antimicrobial resistance is essential in establishing treatment guidelines for urinary tract infections. The aim of this pilot study was to analyse resistance rates of pathogens, across different demographics and determine whether adjustments in empiric therapy should be considered for different age and gender groups.

METHODOLOGY: A 5-year retrospective study included 256 patients hospitalised, under the initial diagnosis of Fever of Unknown Origin who were then subsequently diagnosed with a urinary tract infection at the Clinic for Infectious and Tropical Diseases, Clinical Centre of Serbia. Patients were evaluated using demographic, clinical, and antimicrobial resistance data with appropriate statistical analysis including ANOVA significance testing, univariate, and multivariate analysis.

RESULTS: Resistance rates were above the threshold of 20% for the majority of the antimicrobials tested, the only exception being carbapenems. Amikacin, cefepime, and norfloxacin were agents that could be effectively used as empiric therapy in younger adults with resistance rates of 4.2, 8.0, and 10.0%, respectively. Moderate resistance rates of 17.4% for amikacin and 19.1% for cefepime were observed in the age group 35-64 years. High resistance rates were observed for all antimicrobials among patients 65 years and over. Among male patients, resistance rates to most antimicrobials were high. In female patients, amikacin and cefepime had resistance rates less than 20%. Younger age presented as a negative risk factor for infection by a multi-drug resistant pathogen.

CONCLUSION: Age and gender demonstrated to be significant factors for determining proper empiric therapy; large-scale studies from Serbia are needed to solidify these findings.