Antimicrobial Susceptibility Profile of Fosfomycin and Nitrofurantoin despite Dissemination of Fluoroquinolones and Trimethoprim/ Sulfamethoxazole Resistant Urinary Tract Isolates

Abstract

The widespread growth  of multidrug-resistant (MDR), extended drug resistant (XDR) uropathogens and the shortage of new antimicrobials are the most significant obstacles challenging the treatment of urinary tract infections. The study is aimed to identify the antimicrobial susceptibility profile against MDR and XDR uropathogens. A total of 2485 urine samples were processed from 2267 patients, 361 uropathogens were grown. The antimicrobial susceptibility was determined by the Kirby-Bauer disk diffusion method, following the Clinical and Laboratory Standards Institute’s guidelines. Eighty-nine percent of the samples had Multidrug-resistant microorganisms, while 32% had XDR uropathogens. In comparison to fluoroquinolones and trimethoprim/sulfamethoxazole, fosfomycin and nitrofurantoin demonstrated a significantly higher sensitivity rate against uropathogens, including MDR and XDR uropathogens, in both gender groups with community-acquired and nosocomial UTIs (P<0.001). Fosfomycin revealed the highest sensitivity rate, about 94.8%. Klebsiella pneumonia and E. coli showed the highest resistance rate against fosfomycin in 3.7% and 3.4% of the cases. Nitrofurantoin showed a similar sensitivity rate both in community and hospitalized patients in 86.1%. Fluoroquinolones (61%) and trimethoprim/sulfamethoxazole (86.6%) revealed the highest resistance rate against uropathogens. The prevalence of extended-spectrum beta-lactamases producing pathogens was 10.2%. Fosfomycin and nitrofurantoin revealed a higher sensitivity rate against gram-negative MDR uropathogens in community and nosocomial UTIs compared to fluoroquinolones and trimethoprim/sulfamethoxazole.