Carbapenem-resistant Acinetobacter baumannii strains in the Covid-19 pandemic: 16 S rRNA analysis, carbapenem resistance genes, and antibiotic resistance profiles

Abstract

Acinetobacter baumannii was reported as a frequent pathogen leading to outbreaks of multidrug-resistant organisms both in the intensive care unit (ICU) and in non-ICU units during the coronavirus disease in 2019 (COVID-19). In this study we aimed to examine the phenotypic and molecular characteristics of clinical isolates of carbapenem-resistant A. baumannii (CrAb) obtained from Siirt Training Hospital in Siirt, Turkiye, during the Covid-19 pandemic. In our study, 31.6% of the patients whose culture was taken were Covid-19 positive. Of the 57 CrAb strains tested for antibiotic resistance, 52 (91.2%) showed extensive-drug resistance (XDR), 4 (7%) multi-drug resistance (MDR), and 1 (1.8%) pan-drug resistance (PDR). According to 16 S rRNA analysis, the sequences of the CrAb strains used in our study were 99-100% similar to the 16 S rRNA genes of the A. baumannii strains registered in GenBank. The most frequently detected carbapenem resistance gene in the species in our study was the OXA51 gene (85.7%). It's interesting to note that the blaNDM gene, which has a direct connection to the Indian Subcontinent and has recently been observed in the Middle East but has been rarely detected in Turkiye, was discovered in our study at a high rate. We think that this situation is caused by migration from the Middle East due to war in recent years. Additionally, we believe that horizontal gene transfer between bacteria is the cause of the high frequency of the blaVIM gene, whose source is primarily Pseudomonas species, in A. baumannii species in our study.