Phenotypic Detection of Some Virulence Factors among Hypervirulent Klebsiella pneumoniae and Classic Klebsiella pneumoniae Associated with Urinary Tract Infections

Document Type : Original Article

Authors

Department of Biology, Faculty of Education for Girls, University of Kufa, Najaf, Iraq

Abstract

The present study aimed to investigate prevalence and some virulence factors among hyper virulent Klebsiella pneumoniae (HVKP) and classic Klebsiella pneumoniae (CKP) isolated from urinary tract infections.Three hundred urine samples collected from patients with urinary tract infections were cultured on MacConkey agar for primary isolation of    K. pneumoniae isolates. Vitek 2 Compact System was used for identification of K. pneumoniae. HVKP and CKP were detected by string test.  Some virulence factors (biofilm formation, haemolysin, and urease production) possessed by the bacterial isolates were investigated phenotypically.




           Sixty bacterial isolates belonged to K. Pneumoniae where 15 (25%) isolates belonged to HVKP as viscous string measuring >5 mm in length and 45 (75%) isolates belonged to CKP where viscous string measuring <5 mm in length. The results of haemolysis test showed that 60% of HVKP isolates gave β-haemolysis, while 51.1% of CKP isolates gave β-haemolysis. All bacterial isolates (100%) of HVKP and CKP showed the ability to produce urease. Phenotypically, all HVKP and CKP isolates showed the ability to form biofilm while only 33.3% and 11.1% isolates showed high ability to form biofilm respectively by Tissue Culture Plates methods (TCP). 

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