Distribution of Some Antibiotic Resistance Genes Among Carbapenem-Resistant Acinetobacter Baumannii Isolated From Patients Lying ICU in AL-Najaf /Iraq

Acinetobacter baumannii is a significant nosocomial pathogen, affecting immunocompromised and critically ill patients in intensive care units (ICUs). The emergence of carbapenem-resistant A. baumannii (CRAB) poses a threat due to its resistance to multiple antibiotics. This study investigates the prevalence of carbapenemase-encoding genes among CRAB isolates from ICU patients at AL-Sadder hospital/ Najaf. Eight sputum specimens were collected from ICU patients suspected of A. baumannii. The isolates were identified through morphological, biochemical tests and the Vitek 2 Compact system. Antibiotic sensitivity was determined by the Vitek 2 Compact system (using AST card). only 5 A. baumannii isolates have been identified and all isolates were resistant to most antibiotics and these isolates were detected as CRAB. minocycline and doxycycline showed the lowest resistance, while no resistance to colistin. Phenotypically, all isolates were MBL producers, while none of the isolates had the ability to produce carbapenemase. PCR results showed the prevalence of blaOXA51-like (100%), followed by blaOXA24-like (80%) and blaNDM (40%) while blaGES was detected in 20% of isolates. All CRAB isolates were lacking blaKPC. Sixty percent of MBL producer CRAB were possessed both blaOXA51like and blaOXA24-like, while 20% of MBL producer CRAB possessed blaOXA51-like, bla, blaNDM, and blaOXA24-like, whereas other 20% isolates possessed blaOXA51like and blaNDM. The study highlights the high prevalence of carbapenemase genes among CRAB isolated from ICU patients. These findings underscore the need for effective infection control measures and novel treatment strategies to combat multi-drug resistant A. baumannii in ICU settings.