Evaluation of the susceptibility of Escherichia coli to first-line antimicrobials for the treatment of urinary tract infection

Abstract

Urinary tract infections (UTIs) are frequent in clinical practice, with symptoms such as dysuria, increased urinary frequency, fever and uropathogenic Escherichia coli (UPEC) as the main etiological agent. Treatment of UTIs is often initiated empirically with the use of antimicrobials such as β-lactams, aminoglycosides, sulfonamides, quinolones, fosfomycin and nitrofurantoin. However, with indiscriminate use, bacterial resistance to these drugs has been reported. This study aimed to analyze the susceptibility profile of UPEC isolated from patients with UTI to the antimicrobials listed as the main therapeutic options. The susceptibility profile of 37 isolates determined using the Kirby-Bauer method, provided by a private Clinical Analysis Laboratory in the municipality of Divinópolis-Minas Gerais, was analyzed. The results showed that 48.6% of the isolates were sensitive to all antimicrobials tested, but resistance rates higher than 20.0% were observed for fluoroquinolones and trimethoprim-sulfamethoxazole. Simultaneous resistance to fluoroquinolones and trimethoprim-sulfamethoxazole occurred in 15.7% of isolates, while 8.1% showed resistance to fosfomycin. All isolates were sensitive to nitrofurantoin. Furthermore, isolates classified as multidrug-resistant and producers of the extended-spectrum β-lactamases enzyme (ESBL), although at a low rate, were also detected. The findings indicate that UPEC resistance to antimicrobials commonly used in the treatment of UTIs has been increasing, highlighting the need for preventive measures, continuous monitoring of bacterial resistance and criteria in the prescription of antimicrobials.