Epidemiology and risk factors for carbapenemase-producing Enterobacteriaceae carriage in the hospital: A population-based nested case-control study

Abstract

This study aims to study the epidemiology of Carbapenemase-producing Enterobacteriaceae (CPE) in Hong Kong. This is a longitudinal population-based study reporting monthly CPE incidence rate and a nested case-control study for identifying risk factors for CPE carriage. The cases were patients with at least one CPE positive genotypic test, while the controls were randomly selected from the cohort with negative tests. Up to four controls per case were matched by sex, age group, and admission year-month. The independent risk factors were identified from a conditional logistic regression with potential covariates. From 1st January 2008 to 31st December 2019, 8,588 patients received CPE genotyping tests, and 2,353 had at least one positive result. Class B carbapenemase was the predominant enzyme in the samples (78.6%). The incidence rate increased from 0.04 in 2015 to 1.62 in 2019 per 10,000 person-year. In the nested case-control study, 1709 cases and 6664 controls were matched. Previous use of any beta-lactam antibiotics [Odds ratio:1.37 (1.22-1.53), p<.001] was found as an independent risk factor for carriage of CPE. The carriage of CPE was found with an increasing trend in Hong Kong. Previous use of any beta-lactam antibiotics is a risk factor for CPE. The incidence rate of Carbapenemase-producing Enterobacteriaceae is increasing in Hong Kong, with the predominant enzyme of class B carbapenemase. With multivariable conditional logistic regression, the previous use of any beta-lactam antibiotics was found as an independent risk factor for CPE carriage.