Molecular identification, prevalence, and antibiotic resistance of Pseudomonas aeruginosa isolated from clinical and medical waste samples in Baghdad City, Iraq

Abstract

Identification of P. aeruginosa, determining the prevalence of this pathogen among clinical and medical waste samples, and studying the antibiogram profile of isolates were the objectives of this study. A total of 394 (300 clinical & 94 medical waste) samples were collected during February 2020- October 2020. Morphological characterization, biochemical behavior, and VITEK 2 system identified 14 (5%) and 6 (8.3%) of the presumptive clinical and medical waste isolates respectively as P. aeruginosa. 16S rRNA and gyrB genes confirmed that 8 (2.9%) and 4 (5.6%) clinical and medical waste isolates respectively were P. aeruginosa. Statistically, the difference between the prevalence of P. aeruginosa among clinical and that among medical waste samples was non-significant (P≤0.05). The percentages of resistance showed by P. aeruginosa strains were 91.7% for Ticarciliin; 75% Ticarcillin/Clavulanic acid; 66.7% Ceftazidime, Imipenem, & Ciprofloxacin; 58.3% Gentamicin & Tobramycin; 50% Meropenem; 41.7% Ticarcillin/Clavulanic acid; 33.3% Amikacin, 16.6% Cefepime; and 8.3% for Colistin. In conclusion, medical wastes are a potential source of infection caused by P. aeruginosa, treatment of nosocomial infections should be guided by antibiotic susceptibility testing, and colistin was the most effective antibiotic.