Genotype and Phenotype Investigation of CTX-M Gene among Multidrug Resistant Klebsiella pneumoniae Isolates

Abstract

Beta-lactam resistance is a major clinical problem in treating of Klebsiella pneumoniae infections. Klebsiella pneumoniae (K. pneumoniae) is an opportunistic bacterium that can resist Beta-lactams principally by producing the CTX-M enzymes. The objective of this study was to identify the prevalence of the CTX-M gene in clinical isolates of multidrug resistant (MDR) K. pneumoniae among hospitalized patients in Baghdad metropolis. From 200 various clinical samples (urine, wounds, blood, vaginal, stool, burns and sputum) that collected from hospitals in Baghdad during November 2021 to the end of April 2022, 87 positive K. pneumoniae cultures in total were analyzed. K. pneumoniae was identified from specimens using the CHROM agar orientation medium, biochemical test, VITEK2 system, diagnosis was verified using molecular identification. The antibiotic susceptibility test results showed high resistant to piperacillin, ceftazidime, cefepime, ceftriaxone, ampicillin, cefotaxime while imipenem and meropenem were more effective against the isolates.  All of the K. pneumoniae isolate showed a MDR phenotype and Extended Spectrum Beta Lactamase (ESBLs) producers. The results of the molecular diagnosis of the CTX-M resistance genes showed the presence of this gene in 87 (100%) bacterial isolates.