Extended-spectrum and AmpC ß-lactamases screening and antibiotic resistance profile of <em>E. coli</em> isolated from urine

Abstract

Introduction: Antimicrobial resistance is a global concern since infections by resistant pathogens are associated with higher mortality and morbidity.

Objective: To assess the prevalence of Escherichia coli isolates producing extended-spectrum and AmpC beta-lactamase (ESBL) in urine samples from patients at the Hospital Metropolitano de Santiago in Dominican Republic.

Methods: Pathogen identification and antibiogram were carried out by the automated systems BD Phoenix or Microscan®. General information and past medical history were gathered from patients with a positive urine culture for E. coli. Manual ESBL/AmpC screening was performed with the commercial ESBL+AmpC screen disc kit from Liofilchem Laboratory, Italy.

Results: One or both of the studied phenotypes were present in 36% of the analyzed isolates. Among the risk factors for the detection of E. coli producing ESBL and/or AmpC in urine were male gender, advanced age, placement of urinary catheter, arterial hypertension, neoplasms, and coexistence of two or more comorbidities. Apart from cephalosporins resistance, isolates producing ESBL and/or AmpC also showed higher resistance to other antibiotics, such as gentamicin (66.7%), ciprofloxacin and levofloxacin (83.3%), and ampicillin (91.7%). Furthermore, 85% of the ESBL/AmpC producing samples were multidrug resistant (resistant to 1 or more drugs in at least 3 different antibiotic categories).

Conclusions: The high prevalence of antimicrobial resistance found in this study highlights the importance of implementing national and global measures to tackle the problem, especially in developing countries such as the Dominican Republic, where resources are scarce.