Epidemiology of carbapenem resistant Escherichia coli from piglets

To study the epidemiology of carbapenem resistant E. coli isolates from piglet faecal samples a cross section study was conducted in 10 different locations and total of 673 faecal swabs were collected. On preliminary screening with 1 mg/L imipenem added MacConkey ag 112 E. coli isolates were isolated. The phenotypic screening of 112 isolates with carbapenem antibiotics, aztreonam and moxalactam showed resistance of 18.80 % for meropenem, 9.80% for imipenem, 16.1 % ertapenem, 14.30 % aztreonam and 9.80% for moxalactam. Out of 112 E. coli isolates, 79 (70.54 %) had meropenem MIC between 1 mig and 2 mig /mL (sensitive) and 10 (8.92%) had MIC between 2 and 4 mig/mL (intermediate) and 23 isolates (20.54 %) had meropenem MIC more than 4 mig/mL (resistant). Twenty three isolates were carbapenem resistant, out of which 8 isolates showed keyhole reaction with EDTA and on genotypic screening all were NDM positives. The efflux pump screening of 15 carbapenemase genes negative isolates, 8 isolates showed efflux pump mediated resistance. The remaining 7 isolates showed neither carbapenemase gene nor efflux pump mediated resistance.