Molecular Characterization of Carbapenamases in Hypervirulent Klebsiella pneumoniae Isolates among Pediatric Patients

Abstract

Background: Carbapenem resistant hypervirulent Klebsiella pneumoniae (CR-hvKp) have led to fatal outbreaks. The rapidly increasing detection rate of CR-hvKp in pediatric patients makes the diagnosis of CR-hvKp is critical to improve the clinical utilization of antibiotics. Aim: The present study aims at isolation and antibiotyping of CR-hvKp from clinical samples in Mansoura University Children Hospital. The study also directs to characterize carbapenemases in CR-hvKp isolates. Methodolgy: Eighty five K. pneumoniae isolates were tested for both carbapenems resistance and hypervirulence through detection of peg-344 gene by PCR. Antimicrobial susceptibility testing was done for CR-hvKp isolates by means of Kirby Bauer disc diffusion method. Multiplex polymerase chain reaction (multiplex PCR) was done to detect cabapenemase genes in CR-hvKp isolates. Results: Within the 85 K. pneumoniae isolates, 27strains (27/85; 31.76) were CR-Kp. Among CR-Kp isolates, 20 strains (20/27; 74.07%) were CR-hvKp. All CR-hvKp isolates were resistant to co-amoxiclav, piperacillin-tazobactam, cephalosporines and carbepenams, with variable resistant pattern to aminoglycosides, aztreonam, ciprofloxacin and levofloxacin. Respiratory samples were the main sample type of CR-hvKP isolates (60%), and tracheal intubation was the higher risk factor (50%). Cabapenemase genes were detected in only 13 isolates (13/20; 65%) . The identified carbapenemase genes included bla KPC-2 gene which was the predominant gene (6/13; 46.15%), bla VIM gene was present in 3 isolates (23.08%), and bla IMP and bla NDM genes each was present in 2 isolates (15.38% for each gene). Conclusion: It is critical to improve the clinical responsiveness and management of CR-hvKP infections, especially amongst pediatric patients.