Detection of OXA-23 Among Carbapenem-Resistant Acinetobacter baumannii Isolated From Intensive Care Units of a Tertiary Care Hospital in Pakistan.

Carbapenem-resistant Acinetobacter baumannii (CRAB) has been designated a top-priority critical pathogen by the World Health Organization, and the CDC has also classified it as a serious and immediate public health threat. The Cross-sectional study was conducted to detect the bla OXA-23 gene among carbapenem-resistant Acinetobacter baumannii isolated from clinical specimens in intensive care units. The study was conducted at the Department of Microbiology, Institute of Pathology and Diagnostic Medicine, Khyber Medical University, from January 2024 to December 2024. Phenotypically confirmed Carbapenem-resistant Acinetobacter baumannii isolates were genotypically verified via blaOXA-51 detection, then screened for blaOXA-23 using polymerase chain reaction, and PCR mapping was done for the upstream insertion of ISAba1. blaOXA-23 gene with an upstream insertion of ISAba1 is detected in all 52 (100%) isolates. ST19 is the most commonly identified ST, accounting for 31 (59.6%), followed by ST2 14 (26.9%) and ST1 7 (13.4%). Consequently, these findings emphasize the implementation of targeted infection control measures and routine surveillance screening within high-risk ICU environments to mitigate further transmission.