Authors : Chandran SP, Diwan V, Tamhankar AJ, Joseph BV, Rosales-Klintz S, Mundayoor S, Lundborg CS, Macaden R
Publication Year : 2014
AIM:
This study was done to detect the presence of Escherichia coli resistant to cephalosporins, carbapenems and quinolones in hospital waste-water.
METHODS AND RESULTS:
Waste-waters from a rural (H1) and an urban (H2) hospital were tested for E. coli resistant to cephalosporins, carbapenem and quinolones. Genes coding for chromosomal and plasmid- mediated resistance and phylogenetic grouping was detected by Multiplex Polymerase chain reaction (PCR) and for genetic relatedness by rep-PCR. Out of 190 (H1=94; H2=96) E. coli examined, 44% were resistant to both cephalosporins and quinolones and 3% to imipenem. ESBLs were detected phenotypically in 96% of the isolates, the gene blaCTX-M coding for 87% and blaTEM for 63%. Quinolone-resistance was due to mutations in gyrA and parC genes in 97% and plasmid- coded aac-(6')-Ib-cr in 89% of isolates. Only in one carbapenem resistant E. coli, NDM-1 was detected. Nearly 67% of the isolates belonged to phylogenetic group B2. There was no genetic relatedness among the isolates.
CONCLUSION:
Hospital wastewater contains genetically diverse multidrugresistant E. coli.
SIGNIFICANCE AND IMPACT OF THE STUDY:
This study stresses the need for efficient water-treatment plants in health-care settings as a public-health measure to minimize spread of multidrug-resistant bacteria into the environment.