To assess, in vitro, the ability of E.coli phages to eradicate biofilms built on ureteral stents with an intention to develop an additional treatment option for chronic urinary infection in patients with indwelling ureteral stent.


Phages were grown on isolated E.coli cultures. Phage host range of infection was determined with plaque assay method. The urine stability of phages was assessed. Biofilm model was built separately on 96 well plates and on ureteral stent. Following biofilm infection, the phage lytic with and without ampicillin was assessed by colony forming units (CFU) test and scanning electron microscopy (SEM).


Ampicillin resistant, E.coli strain O5 was found as sensitive to a group of phages designated ECOY 1-8 and was therefore selected as a study strain. ECOY5 was found to be stable in urine and was selected as a study phage. In the study group, the CFU test showed 10- fold and 100- fold decrease in E.coli CFU growth for well plate and stent models respectively. The lytic effect of phage treatment was visualized on SEM images.


Use of the ECYO5 phage alone or in combination with ampicillin appears to be very effective in breaking down the biofilm of E.coli. Further research is needed to develop phage-based products for stent associated infections including other uropathogens.

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