Extended-spectrum beta-lactamase-producing Enterobacteriaceae carriage upon hospital admission: prevalence and risk factors

Summary

The aim of this study was to assess the value of surveillance cultures in identifying extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL) carriers upon admission to hospital, and to identify risk factors for carriage. This prospective cross-sectional study included all hospital admissions over one week.

Of 525 patients screened, 56 were positive for ESBLs. Half were only identified through screening. Four independent risk factors were identified: nursing home residency, hospitalization in the previous year, prior antibiotic treatment and prior ESBL carriage. Over 50% of the screened patients had at least one risk factor. By screening this targeted population, 87.5% of positive patients would have been identified.

Introduction

Antibiotic stewardship and infection control are considered to be the two main strategies to control the spread of multi-drug-resistant bacteria, including extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL).¹ However, debate continues regarding the role of patient-to-patient spread, and the effectiveness of infection control in reducing ESBL infections and colonization.2, 3 The use of surveillance depends on several factors, one of which is the proportion of patients that would be missed by relying solely on clinical cultures (undetected ratio). The aim of this study was to assess risk factors for colonization with ESBLs, and to find the undetected ratio of patients carrying ESBLs.