Prevalence and antibiotic resistance pattern in Pseudomonas aeruginosa isolates from chronic otitis and pyoderma samples of dogs in Andhra Pradesh, India

INTRODUCTIONPseudomonas aeruginosa, a superbug is a threatful pathogen to both humans and animals as it is considered a multi-drug resistant bacterium [1] owing to its resistance to almost all commonly used antibiotics.Acquiring drug resistance by a bacterium is multifactorial and is attributed to the misuse of antibiotics, inappropriate dosage as well as the ability of the bacterium to develop various fighting mechanisms to surpass the effects of antibiotics [2].The other probable reason for the resistance of P. aeruginosa was due to low membrane permeability attributed to intrinsic resistance and synthesis of AmpC beta-lactamase enzymes [3].In dogs, P. aeruginosa is responsible for 20% of infections which mainly include otitis, skin and wound infections, urinary tract ABSTRACT: Pseudomonas aeruginosa is an ESKAPE bacterial pathogen known to be the reason for causing recurrent otitis and suppurative skin infections in dogs.The current study was undertaken to detect the prevalence of antibiotic-resistant P. aeruginosa isolates from chronic otitis and pyoderma samples of dogs.A total of ninety-seven (n=97) samples were collected, from otitis cases (n=45) and pyoderma cases (n=52).Preliminarily, cultural, and biochemical tests were carried out for the isolation of P. aeruginosa, and molecular tests like Polymerase Chain Reaction (PCR) using species-specific 16S rRNA primers that yielded a specific PCR product size of 956bp were utilized as a confirmative test in detecting 35(36.08%)isolates of P. aeruginosa from suspected cases.An antibiotic sensitivity test was performed on all 35 positive P. aeruginosa isolates by Kirby-Bauer disc diffusion method using a panel of 10 different antibiotics.The results revealed that P. aeruginosa has the highest resistance to tetracycline (97.14%) and the highest sensitivity to imipenem (88.58%).The Multiple Antibiotic Resistance (MAR) index of all the positive isolates ranged between 0.5-1.All 35 (100%) positive P. aeruginosa isolates were found to be multi-drug resistant (MDR) and 30 (85.71%) isolates were extensively drug-resistant (XDR).In conclusion, this study revealed a high prevalence of MDR and XDR strains of P. aeruginosa in the collected dog samples.