Performance of different culture methods and of a commercial molecular assay for the detection of carbapenemase-producing Enterobacteriaceae in nursing homes and rehabilitation centers

摘要

Over the last years carbapenemase-producing Enterobacteriaceae (CPE) have beenincreasingly detected among patients in acute care hospitals but also in long-termcare facilities.In this point prevalence survey, residents from three nursing homes and patients in onerehabilitation center were screened for asymptomatic intestinal carriage of CPE byrectal swabs. The first objective was to evaluate the hypothesis of the establishment ofa CPE reservoir in a geriatric/chronic care population. Secondly, we evaluated thecomparative performances of different culture methods (ChromID®CARBA,ChromID®OXA-48, MacConkey with temocillin/meropenem, ertapenem enrichmentbroth) and of a commercial molecular assay (Check-Direct CPE).From the 257 included residents, only one had evidence for CPE carriage. From therectal swabs of this resident, an OXA-48 producing Klebsiella pneumoniae could beisolated and was confirmed by a molecular assay both on the strain and on the rectalswab. Specificity of the different culture methods and Check-Direct CPE PCR was atleast 97%. Neither enrichment broth nor prolonged incubation up to 48 hours didincrease the yield of CPE.This point prevalence survey shows a low CPE prevalence of 0.39%. Larger scaledstudies are needed to confirm the role of chronic care settings as secondary CPE