Antimicrobial Resistance Profiles and Co-Existence of Multiple Antimicrobial Resistance Genes in -Harbouring Colistin-Resistant Isolates Recovered from Poultry and Poultry Meats in Malaysia.

The co-existence of the colistin resistance () gene with multiple drug-resistance genes has raised concerns about the possibility of the development of pan-drug-resistant bacteria that will complicate treatment. This study aimed to investigate the antibiotic resistance profiles and co-existence of antibiotic resistance genes among the colistin-resistant isolates recovered from poultry and poultry meats. The antibiotic susceptibility to various classes of antibiotics was performed using the Kirby-Bauer disk diffusion method and selected antimicrobial resistance genes were detected using PCR in a total of 54 colistin-resistant isolates including (. ) (n = 32), spp. (n = 16) and (. ) (n = 6) isolates. Most of the isolates had multi-drug resistance (MDR), with antibiotic resistance against up to seven classes of antibiotics. All -harbouring, colistin-resistant isolates showed this MDR (100%) phenotype. The harbouring . isolates were co-harbouring multiple antibiotic resistance genes. The seven most commonly identified resistance genes (, , , , , , ()) were detected in an -harbouring . isolate recovered from a cloacal swab. The harbouring spp. isolate recovered from poultry meats was positive for , , , , and () genes. In conclusion, the colistin-resistant with genes co-existing multiple clinically important antimicrobial resistance genes in poultry and poultry meats may cause potential future threats to infection treatment choices in humans and animals.