Detection of Biofilm Formation in Classical and Hypervirulent Klebsiella pneumoniae

Klebsiella pneumoniae has considered as a relevant healthcare-associated pathogen, its risk of infections is increasing in the presence of medical devices. K. pneumoniae is known for its ability to form biofilm on biotic and abiotic surfaces. Biofilm of K. pneumoniae assists in bacterial protection from host immune responses and antibiotics. Hypervirulent Klebsiella pneumoniae (hvKp) emerges as a new pathotype, which first appeared in Asian Pacific Rim but spread globally. Thus, this study aimed to investigate the ability of K. pneumoniae including hvKp and potential hvKp isolates to form biofilm. One hundred isolates of K. pneumoniae were collected from different hospitals in Baghdad city. These isolates were identified by phenotypic characterization on selective agar plates, biochemical tests, VITEK II, and molecular identification. Biofilm formation was tested in these isolates by two methods, congo red and Tissue Culture Plate method. In congo red method, 33% of the isolates were biofilm producer and (63%) can form biofilm by TCP method divided as: 14% strong, 15 moderate, 34% weak, and 37% non-biofilm producer. The hvKp and potential hvKp isolates showed a variable ability to form biofilm as classical K. pneumoniae.