Burden of Carbapenem Resistant Acinetobacter baumannii Harboring blaOXA Genes in the Indian Intensive Care Unit

Abstract

Objectives: The World Health Organization (WHO) mentioned Acinetobacter baumannii as a “priority of concern” in 2017. Acinetobacter baumannii generally infects immunocompromised patients and causes various nosocomial infections in the intensive care unit (ICU) such as bacteremia, meningitis, ventilator-associated pneumonia, other respiratory infections, and surgical site infections. As oxacillinase has weak hydrolysis activity, more work was needed on this class-D beta-lactamase. Hence, the current Systematic review focuses on the A. baumannii’s oxacillinase (Class-D beta-lactamases) enzyme and its variants collected during 2013–2020 in India for complete genome sequencing. Method: This Systematic review has been done according to PRISMA guideline 2020. We have used the Bacterial and Viral Bioinformatic Resource Centre (bv-brc.org) system for comparative genome analysis. The protein Basic Local Alignment Search Tool (BLAST) was used to identify similarities between sequences, in which BLOSUM62 was used as a scoring matrix. Clustal-W was used for multiple sequence alignment. A phylogenetic tree of the blaOXA gene family has been constructed using MEGA version 11. Result: In India during 2013–2020, for genome sequencing of A. baumannii, the highest number of samples was collected from blood (36%), following the ETA (30%). The average G+C % content was 38.95%. Among the 339 A. baumannii isolates, a maximum of 189 (55.75%) strains caused pneumonia, whereas 113 (33.33%) strains were involved in bacteremia. Carbapenems seemed effective, but resistance against them was higher. Among all A. baumannii genomes, bla-OXA-23 had the highest frequency (314; 92.62%), followed by bla-OXA-66 (241; 71.09%) in India. Conclusion: Our findings indicated that a high percentage of A. baumannii strains that produce oxacillinases exist in India, emphasizing the necessity for indigenous molecular surveillance to assist effective management and preventative initiatives. Comparative genomics and next-generation sequencing will offer tremendous potential for tracking and regulating the spread of this dangerous bacterium.