Molecular characterization of Klebsiella pneumoniae strains isolated from critically ill patients in a tertiary care hospital in Damietta, Egypt

Background: Klebsiella pneumoniae is a common cause of nosocomial infections. Aim: To investigate the virulence-associated characters and antibiotic resistance of K. pneumoniae from patients in intensive care units. Methods: Fifty (50) clinical isolates of K. pneumoniae were tested for antibiotic sensitivity and virulence-associated factors were examined genotypically and phenotypically. Results: Several resistance patterns were detected, including Multidrug Resistance (MDR) was 72 % and Extensive Drug Resistance (XDR) was 28% of the strains. The detection of the virulence and drug-resistant genes was done using the polymerase chain reaction (PCR) technique. The most frequent β-lactam resistance gene was blaSHV-1 (88%), followed by blaTEM (78%), and blaCTX-M-1 (48%). Carbapenemase gene bla OXA-48 was discovered in (64%) of the strains. The studied virulence-associated genes were fimH (88%), luxS (62%), and rmpA (26%). Using crystal violet assay, it was discovered that 88% of the strains could form biofilms. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) was used for molecular typing. Hierarchical clustering and ERIC-PCR-based genotyping of K. pneumoniae strains showed a relationship between patient samples and location, indicating clonal association with likely transferring genes of antibiotic resistance. Conclusion: Our study might contribute to better patient care and infection control measures in Egypt. Also, it may aid in the establishment of national health strategies about nosocomial illnesses.