Investigation of Multidrug-Resistant Klebsiella pneumoniae and Acinetobacter baumannii Isolated from Inpatients at Al-Nasiriyah Teaching Hospital

This study aimed to determine the prevalence, phenotypic characteristics, molecular identification, and antibiotic resistance pattern of both of A. baumannii and K. pneumoniae in inpatients at Al-Nasiriyah Teaching Hospital, Iraq. A total of 150 clinical specimens were obtained and processed for A. baumannii and K. pneumoniae isolation using typical microbiological, PCR and DNA sequencing techniques. The antimicrobial susceptibility testing was conducted by using VITEK-2. The results revealed a 23% (35/150) prevalence of A. baumannii, and the same ratio for K. pneumoniae was identified and diagnosed; however, the remaining gram-negative isolates represented 54%. PCR confirmed these isolates as A. baumannii and K. pneumoniae using specific primers. The antibiogram profile revealed high susceptibility to tigecycline (94.3%) by all of our tested isolates. There was a high prevalence of multidrug resistance among both species, with A. baumannii demonstrating complete resistance to several key antibiotics. Sample-type-specific patterns were also identified. Both bacterial species can be classified as MDR. The significant burden of MDR and XDR profiles among A. baumannii and K. pneumoniae in these inpatient samples emphasizes the need for optimized experimental therapy and rigorous administration in Thi-Qar.