Detection of Carbapenem-Resistant Organisms in the Intensive Care Unit of University of Calabar Teaching Hospital, Cross River State

Carbapenem-resistant organisms (CROs) have emerged as critical pathogens in intensive care units (ICUs) globally, representing a severe threat to patient safety in settings where last-resort antibiotics lose efficacy. This study detected and characterized CROs from clinical specimens of patients admitted to the ICU of University of Calabar Teaching Hospital (UCTH), Cross River State, South South Nigeria. Tracheal aspirates, blood cultures, catheter-associated urine cultures, and wound swabs from 80 ICU patients were processed over four months. Carbapenem resistance was initially screened by disk diffusion using meropenem and ertapenem disks, and confirmed by modified carbapenem inactivation method (mCIM) and PCR for bla-OXA, bla-KPC, and bla-NDM genes. Results showed a CRO prevalence of 26.25 percent among ICU patients, with Klebsiella pneumoniae (47.6%), P. aeruginosa (28.6%), and Acinetobacter baumannii (23.8%) as the predominant species. bla-OXA-48 was the most frequently detected resistance gene (52.4%), followed by bla-NDM (33.3%). Length of ICU stay exceeding seven days was the strongest predictor of CRO acquisition. These findings represent an alarming emergence of last-resort drug resistance in a South South tertiary ICU and demand urgent implementation of carbapenem-sparing treatment bundles, active surveillance cultures, and contact precautions for CRO-positive patients. Keywords: carbapenem resistance, ICU, Klebsiella pneumoniae, NDM, Cross River State.