Comparative analysis of virulence factors, capsular types, and antimicrobial resistance in hypervirulent and classical Klebsiella pneumoniae clinical isolates

Along with the documented global spread of growing antimicrobial resistance, the Klebsiella pneumoniae (K. pneumoniae) is involved in serious clinical infections. The study investigates the ability of biofilm formation, virulence factors, capsular genes, and antibiotic resistance characteristics in hypervirulent K. pneumoniae (hvKp) and classical K. pneumoniae (cKp) isolates from diverse clinical specimens. A total of ۸۵ Klebsiella pneumoniae isolates were collected from patients in hospitals in Erbil, Iraq, between July ۲۰۲۳ and February ۲۰۲۴. Several phenotypic tests, antibiotic resistance pattern and frequency of capsular genes (K۱ and K۲) and virulence-related genes (enB, kfu, mrkD and rmpA) have been compared among hypervirulent and classical variants. The results revealed that ۴۴.۷% were classified as hvKp, showing higher frequencies of capsular and virulence genes K۱ ۲۳.۷%, K۲ ۵۲.۶%, kfu ۴۷.۴%, rmpA ۹۲.۱%, enB ۷۶.۳%, and mrkD ۷۶.۳%), whereas ۵۵.۳% were cKp, with lower gene frequencies (K۱ ۱۲.۸%, K۲ ۴۸.۹%, kfu ۲۵.۵%, rmpA ۸.۵%, enB ۶۸.۱%, and mrkD ۵۱.۱%). The hvKp had lower resistance rates compared to cKp,/ except for ampicillin and amoxicillin/clavulanic acid. The prevalence of capsular and virulence-related genes that were tested was greater in hvKp than in cKp, despite the lower frequency of hvKp variants. In conclusion, hvKp isolates exhibit a higher prevalence of capsular and virulence-related genes but lower antimicrobial resistance compared to classical cKp. These findings highlight the distinct pathogenic and resistance profiles of hvKp and cKp, emphasizing the need for continued surveillance and tailored infection control strategies to manage multidrug-resistant strains.

کلیدواژه ها:

Antimicrobial resistance ، Biofilm formation ، Classical (cKp) ، Hypervirulent (hvKp) ، Klebsiella pneumoniae ، Virulence factor