In vitro efficacy of fosfomycin against E. coli and prevalence of MDR and XDR E. coli isolates from UTI Patients

Objective:  The efficacy of fosfomycin against ESBL and/or carbapenem-resistant E. coli isolated from urine samples was determined. Methodology: Three hundred fifty (350) urine samples were collected from the patients having UTI visited to the department of Urology, JPMC, Karachi. The CLED agar was used for the primary isolation of uropathogens. Regular antimicrobial sensitivity testing was conducted in accordance with CLSI standards, and the minimum inhibitory concentration (MIC) of fosfomycin was assessed using E-strips. Results: Out of 350 urine samples 213 (60.85%) were E. coli.  Patients with E. coli had an average age of 38.75 15.01 years.  Females are more prone to have UTI 146(68.54%). E. coli was highest among uropathogens having frequency of 213(60.85%). E. coli manifest highest resistance to ampicillin 187(87.79%) and low resistance to meropenem 12(5.63%), imipenem 15(7.51%) and fosfomycin 21(9.85%). The overall carbapenem resistant E. coli was 9(6.4%) and majority of (61.5%) fosfomycin resistant E. coli, MIC value was >1024µg/ml. Isolates were categories in the non-MDR, MDR and XDR. Most of the isolates were MDR (53%), followed by the non-MDR (35%) and XDR (11%). Conclusion: In conclusion present study suggests that fosfomycin is still effective against E. coli. More than 50% E. coli isolates were MDR and it’s an alarming situation for urologist.