In vitro Activity of Ceftolozane/Tazobactam for the Treatment of Complicated Urinary Tract Infections by Escherichia coli in the Era of Antibiotic Resistance “Rejuvenate the mystery”

Background: Urinary tract infections are found to be commonest bacterial infections across the globe. Various studies have demonstrated high prevalence rate of UTIs in Pakistan. Multiple broad spectrum antibiotics are being used for the treatment of UTI but the resistance by the pathogen against these drugs is increasing worldwide. As the resistance in the organisms is increasing day by day, and it is now hall mark and matter of concern for clinicians to treat uropathogenic E. coli, so there is a pertinent need to explore new sensitive antibiotics or alternative options to manage the disease.

Aims: To determine the pathogen burden and susceptibility pattern of ceftolozane/tazobactam against MDR E. coli isolates from clinical specimens of urinary tract infections in Karachi.

Study Design: It was an in-vitro clinical study.

Study Settings: The study was conducted in department of Pharmacology, Baqai Medical University and isolates were collected from Microbiology laboratory of Karachi.

Methodology: On the basis of identification methods, one hundred and fifty (150) strains of E. coli were isolated from 650 specimen of urine. Clinical isolates were identified by standard and specific microbiological methods. The antibiotic susceptibility pattern was determined by Kirby Bauer Disc diffusion method. Samples were processed as per procedures defined by Clinical and Laboratory Standards Institute (CLSI) guidelines 2018.

Results: Out of 150 isolates of E. coli, 95 (63.3%) were MDR E. coli. majority of the cases were obtained from age group 61-80 year (32.6%). Highest sensitivity was seen by ceftolozane/tazobactam (96%) followed by ceftriaxone (88%). Least sensitivity was observed with Imipenem (13.70%). However increased trend of resistance was seen among all empirical used drugs.