Hemagglutination and biofilm formation as virulence markers of uropathogenic Escherichia coli in acute urinary tract infections and urolithiasis

INTRODUCTION: Urinary tract infections (UTI) are a major public health concern in developing countries. Most UTIs are caused by E. coli, accounting for up to 90% of community-acquired UTIs (CAUTI). Recurrent UTI is considered as a major risk factor for urolithiasis. Virulence factors like adhesins and biofilm have been extensively studied by authors on UPEC isolated from recurrent UTI. The studies on isolates from infection stones in kidney are scanty. In a prospective study, we aimed to determine the expression of Haemagglutinins, (Type 1 and P fimbriae), Biofilm production and resistance pattern to common antibiotics of Uropathogenic E.coli (UPEC) isolates from Community acquired Acute Urinary Tract Infection(CAUTI) and Urolithiasis. MATERIALS AND METHODS: A total of 43 UPEC isolates, 23 mid-stream urine (MSU) samples from patients with CAUTI attending Out Patient Departments and 20 from renal calculi of urolithiasis patients at the time of Percutaneous nephrolithostomy (PCNL) were included in the study and the expression of Haemagglutinins,(Type 1 and P fimbriae), Biofilm production and resistance pattern to common antibiotics was assessed. RESULTS: A total of 43 UPEC isolates 23 from CAUTI and 20 from renal calculi were tested for production of biofilm and hemagglutinins. In CAUTI, biofilm producers were 56.52% and hemagglutinins were detected in all isolates 100%. In urolithiasis, biofilm producers were 100% but hemagglutinins were detected only in 70% of isolates. All isolates were resistant to multiple antibiotics used. CAUTI isolates were susceptible to 3(rd) generation cephalosporins, whereas urolithiasis isolates were resistant to 3(rd) generation cephalosporins and 25% were Extended Spectrum Beta Lactamases ESBL producers. CONCLUSIONS: HA mediated by type 1 fimbriae plays an important role in CAUTI (P < 0.001 highly significant), whereas, in chronic conditions like urolithiasis, biofilm plays an important role in persistence of infection and the role of hemagglutinins is less.