Screening of nursing home residents for colonization with carbapenem-resistant Enterobacteriaceae admitted to acute care hospitals: Incidence and risk factors

Background There are increasing reports of multidrug-resistant gram-negative bacilli in nursing homes and acute care hospitals. Methods We performed a point prevalence survey to detect fecal carriage of gram-negative bacteria carrying carbapenem resistance genes or which were otherwise resistant to carbapenem antibiotics among 500 consecutive admissions from local nursing homes to 2 hospitals in Providence, Rhode Island. We performed a case-control study to identify risk factors associated with carriage of carbapenem-resistant Enterobacteriaceae (CRE). Results There were 404 patients with 500 hospital admissions during which they had rectal swab samples cultured. Fecal carriage of any carbapenem-resistant or carbapenemase- producing gram-negative bacteria was found in 23 (4.6%) of the 500 hospital admissions, including 7 CRE (1.4%), 2 (0.4%) of which were Klebsiella pneumoniae carbapenemase (ie, blaKPC ) producing (CPE) Citrobacter freundii , 1 of which was carbapenem susceptible by standard testing methods. Use of a gastrostomy tube was associated with CRE carriage ( P = .04). We demonstrated fecal carriage of carbapenem-resistant or carbapenemase-producing gram-negative bacteria in 4.6% of nursing home patients admitted to 2 acute care hospitals, but only 0.4% of such admissions were patients with fecal carriage of CPE. Use of gastrostomy tubes was associated with fecal carriage of gram-negative bacteria with detectable carbapenem resistance. Conclusion CRE fecal carriage is uncommon in our hospital admissions from nursing homes.