Prevalence of faecal carriage of Carbapenemase Producing Enterobacteriaceae in healthy Indian subjects from the community.

PURPOSE: Faecal carriage of carbapenemase-producing Enterobacterales (CPE) has been extensively investigated in hospitalized patients, but limited data is available on the carriage rate in healthy individuals in India.

METHODS

A total of 1000 stool samples were screened for CPE from healthy individuals in Chennai (n ​= ​50), Hyderabad (n ​= ​184) and Mumbai (n ​= ​766). Diluted stool samples were cultured on chromID CARBA SMART plates. Growing colonies were screened for CPE by RAPIDEC® CARBA NP Test and minimum inhibitory concentration (MIC) of imipenem by E-Test. PCR was performed for confirmation of CPE genes.

RESULTS

Out of the 1000 stool samples tested, 6.1% were positive for CPE. A total of 64 carbapenem resistant isolates (56 ​E.coli, 4 Klebsiella pneumoniae, 3 Enterobacter cloacae and 1 Citrobacter freundii) were recovered from ChromID CARBA SMART biplate. Carbapenemase production was identified in 57/64 isolates by RAPIDEC® CARBA NP test. PCR analysis showed 28 blaNDM-1 and 33 blaOXA48. Three remaining isolates (2 ​E.coli, 1 ​K.pneumoniae) were negative for the tested carbapenemase genes. Interestingly, out of these 61 PCR positive isolates, 49.1% displayed imipenem MIC within the susceptibility range on the basis of CLSI interpretative criteria.

CONCLUSIONS

Faecal carriage of CPE among healthy individuals was 6.1%. Comprehensive measures to improve the sanitation scenario and implementation of National AMR action plan are needed to prevent further generation and dissemination of carbapenem resistant Enterobacterales (CRE).