hypervirulent klebsiella pneumoniae: biofilm formation, capsular type, virulence genes, and genotyping in amol hospitals, northern iran

Background: klebsiella pneumoniae is a significant opportunistic pathogen, primarily responsible for hospital-acquired pneumonia and other severe infections, particularly in immunocompromised individuals. objectives: this study investigated the biofilm formation, hypervirulent k. pneumoniae (hvkp) identification, and virulence gene detection among k. pneumoniae isolates from various hospital units and sample types. methods: after dna extraction from 70 k. pneumoniae isolates, capsular types were identified using specific methods. the biofilm assay categorized isolates based on biofilm formation strength. the string test identified hvkp isolates, while virulence genes were detected using polymerase chain reaction (pcr). random amplified polymorphism dna-pcr (rapd-pcr) fingerprinting with two primers was used to identify genotypic variations. results: in total, 44 (62.85%) hvkp isolates were identified, with a significant correlation to strong biofilm formation (p < 0.05). the entb and mrkd virulence genes were present in all isolates. there was no significant relationship between virulence gene patterns and hvkp status, hospital unit, or sample type (p > 0.05). the rapd-pcr fingerprinting identified 25 and 19 clusters, respectively, showing significant relationships with sample type, biofilm production, and specific virulence gene patterns. conclusions: the study highlighted the high prevalence of biofilm production and hvkp among isolates. significant associations were identified between certain genotypes, sample types, and biofilm production. these findings underscore the importance of monitoring biofilm formation and virulence factors in clinical isolates to inform infection control strategies.