Epidemiology and Resistance Levels of Enterobacteriaceae Isolates from Urinary Tract Infections Expressed as Multiple Antibiotic Resistance (MAR) Indices

Márió Gajdács

doi:10.9734/jpri/2019/v29i330238

Abstract

Aims: To assess the epidemiology of UTIs affecting inpatients and outpatients and the antibiotic resistance levels, expressed as multiple antibiotic resistance (MAR) indices from the isolated species at a tertiary-care hospital in Hungary, during a 10-year study period. Study Design: Retrospective microbiological study. Place and Duration of Study: 1st of January 2008 - 31st of December 2017 at the University of Szeged, which is affiliated with the Albert Szent-Györgyi Clinical Center, a primary- and tertiary-care teaching hospital in the Southern Great Plain of Hungary. Methodology: Antimicrobial susceptibility testing (AST) was performed using disk diffusion method and when appropriate, E-tests on Mueller–Hinton agar (MHA) plates. The multiple antibiotic resistance (MAR) index of the isolates was determined. Results: During the 10-year study period, the Institute of Clinical Microbiology received 21,150 urine samples from outpatient clinics and 19,325 samples from inpatient departments that turned out to be positive for a significant urinary pathogen. Out of the positive urine samples, E. coli represented the overwhelming majority of all positive urine samples. The resistance levels in inpatient isolates were higher than in the outpatient isolates (average MAR indices: 0.347 vs. 0.410, 0.267 vs. 0.435 and 0.318 vs. 0.473 for the E. coli/Klebsiella, CES and Proteae group, respectively). Conclusion: As the therapeutic options are becoming increasingly limited in the current antibiotic resistance climate, more effort should be put into the prudent use of antibiotics and the development of novel antimicrobial agents.

Highlights

Urinary tract infections (UTIs) are some of the most common infections in human healthcare, both in community (10–30% of infections in primary healthcare) and nosocomial settings (30–40%) [1,2]
As the therapeutic options are becoming increasingly limited in the current antibiotic resistance climate, more effort should be put into the prudent use of antibiotics and the development of novel antimicrobial agents
UTIs are most frequently caused by members of the Enterobacteriaceae family: typical pathogens include uropathogenic Escherichia coli and Klebsiella spp., the Proteus-Providencia-Morganella species, Citrobacter-EnterobacterSerratia species have emerged as increasingly relevant Gramnegative pathogens [4,5,6,7]

Summary

Introduction

Urinary tract infections (UTIs) are some of the most common infections in human healthcare, both in community (10–30% of infections in primary healthcare) and nosocomial settings (30–40%) [1,2]. UTIs are most frequently caused by members of the Enterobacteriaceae family (or more recently, the Enterobacterales order): typical pathogens include uropathogenic Escherichia coli and Klebsiella spp., the Proteus-Providencia-Morganella species (the Proteae tribe), Citrobacter-EnterobacterSerratia species (so-called CES pathogens) have emerged as increasingly relevant Gramnegative pathogens [4,5,6,7]. E. coli and Proteus spp. possess fimbria, allowing for attachment to epithelial cells; the resulting production of IL-6 and IL-8 causes epithelial cell desquamation. The therapy of UTIs is an increasingly complex challenge for clinicians, due to the increasing levels of antibiotic resistance [8,9]. The emergence of multidrug resistance (MDR) and extensive drug resistance (XDR) in urinary pathogens, together with pre-existing, genetically encoded resistance mechanisms means that these pathogens may be resistant to a broad range of antibiotics [10,11]

Methods

Results

Conclusion