The Detection of Fosfomycin-Modifying Enzymes (fos) in Uropathogenic Enterobacterale, Azerbaijan, Iran.

Enterobacteriaceae is the most common agent of urinary tract infections (UTIs). Multidrug resistant (MDR) and XDR (extensively drug-resistant) Enterobacteriaceae in UTIs have increased in the world. The present study aimed to study the fosfomycin resistance frequency and the fosfomycin resistance genes among Enterobacteriaceae isolated from UTIs. The urine was collected and cultured in the standard protocol. To determine the susceptibility testing to fosfomycin in 211 isolates, agar dilution and disk agar diffusion methods were used. MDR was nonsusceptibility to at least one agent in three or more antimicrobial categories. The fosfomycin resistance genes were also evaluated by PCR. The frequency of resistance to fosfomycin was in 14 (6.6%) and 15 (7.1%) isolates by the disk agar diffusion and MIC assays, respectively. However, the MIC₅₀ and MIC₉₀ existed at 8 μg/mL and 16 μg/mL, respectively. The MDR was found in 80%. The frequencies of fosfomycin resistance genes were 5 (33.3%), 3 (20%), 2 (13.3%), 1 (6.6%), and 1 (6.6%) for fosC, fosX, fosA3, fosA, and fosB2, respectively. The fosB and fosC2 were not found. A low resistance rate to fosfomycin is observed. Fosfomycin is still one of the most effective and valuable alternative antibiotics against MDR Enterobacteriaceae isolated from UTIs in our region.