Screening for carriers of carbapenemase producing Enterobacteriaceae in critical care units

Abstract

Background: The increasing cases of carbapenemase resistant Enterobacteriaceae (CRE) across the world is a cause of concern. Asymptomatic carriage of CRE in critical care units is a menace to infection control. Aims: This study determines the carriage rate of CRE in patients admitted to the intensive care units (ICU's) and evaluates the potential risk factors, leading to colonization in patients with CRE. Materials and Methods: Sixty rectal swabs from patients in the ICU's were screened for carriage of CRE. The samples were inoculated onto ChromID CARBA SMART bi-plate. The organisms showing color appearances as per the manufacturer's instructions were considered as CRE. Routine disk diffusion technique was also employed and CRE was defined as an organism belonging to the Enterobacteriaceae family which was resistant to either imipenem or meropenem. Results: The organisms isolated were identified and the percentage of carriage of carbapenem-resistant organisms was 12 (20%), of which Klebsiella pneumoniae was 4 (33.3%), Escherichia coli 6 (50%), Citrobacter freundii 1 (8.3%), and Enterobacter spp. 1 (8.3%). Out of these, 2 (3.3%) showed OXA 48 type resistance seen with K. pneumoniae and E. coli. Prior hospitalization, the use of high-end antibiotics and patients who have undergone surgeries were the most common potential risk factors for colonization with CRE. Conclusion: The prompt detection of CRE by routine screening using cost-effective methods and reduction of potential risk factors for gut colonization reduce the transmission of drug resistance in any hospital setting and pave the way for better antibiotic stewardship and appropriate contact isolation precautions.

Keywords

• asymptomatic carriage
• carbapenemase
• enterobacteriaceae
• resistance
• screening