Prevalence of <i>BlaOXA-48, BlaDIM-1</i>, and <i>BlaKPC1 </i>genes in carbapenem-resistant <i>Pseudomonas </i>species isolated from wastewater and clinical samples from Baghdad hospitals

Antibiotic resistance poses a significant threat to public health, driven by misuse and overuse of antibiotics in healthcare and agriculture. Among Gram-negative bacteria, carbapenem-resistant Pseudomonas species are particularly worrisome due to their ability to harbor resistance genes such as blaOXA-48, blaDIM-1, and blaKPC1. The present study aimed to determine the prevalence of blaOXA-48, blaDIM-1, and blaKPC1 genes in Pseudomonas isolates from wastewater and clinical samples collected from two Baghdad hospitals. Sixty-nine (69) samples, including blood, urine, wounds, ear swabs, and wastewater, were cultured and subjected to morphological and biochemical analyses. Antibiotic susceptibility testing was conducted using the VITEK 2 system. Molecular analysis was conducted through the polymerase chain reaction (PCR) to detect the most common resistance genes (blaOXA-48, blaDIM-1, and blaKPC1). Out of sixty-nine samples, thirty-two Pseudomonas isolates were identified, with Pseudomonas aeruginosa accounting for 65.62% of isolates. Other isolates included P. putida (21.5%), P. sutzeri (21.5%), P. fluorescens (6.25%), and P. lutrola (3.13%). Antibiotic susceptibility testing revealed 31.25% of isolates were resistant to carbapenems, classifying them as multidrug-resistant (MDR). Polymerase chain reaction analysis demonstrated the presence of blaOXA-48 and blaDIM-1 genes in 15.62 and 6.25% of isolates, respectively, with one isolate harboring both genes. No blaKPC1 gene was detected. The present study highlights the alarming dissemination of carbapenem resistance genes in clinical and environmental settings, posing a significant challenge to effective treatment. Findings underscore the importance of molecular epidemiological surveillance to inform targeted interventions and mitigate the spread of resistance in resource-limited settings like Baghdad.