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

ABSTRACT: Objectives: This study aims to study the epidemiology of carbapenemase-producing Enterobacteriaceae (CPE) in Hong Kong. Methods: 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. Results: From 1 January 2008 to 31 December 2019, 8588 patients received CPE genotyping tests, and 2353 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 < 0.001) was found as an independent risk factor for carriage of CPE. Conclusion: 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.