title: Bacteriophages as Potential Treatment for Urinary Tract Infections.
abstract: BACKGROUND
  Urinary tract infections (UTIs) are among the most prevalent microbial diseases and their financial burden on society is substantial. The continuing increase of antibiotic resistance worldwide is alarming so that well-tolerated, highly effective therapeutic alternatives are urgently needed.
  
  
  OBJECTIVE
  To investigate the effect of bacteriophages on Escherichia coli and Klebsiella pneumoniae strains isolated from the urine of patients suffering from UTIs.
  
  
  METHODS
  Forty-one E. coli and 9 K. pneumoniae strains, isolated from the urine of patients suffering from UTIs, were tested in vitro for their susceptibility toward bacteriophages. The bacteriophages originated from either commercially available bacteriophage cocktails registered in Georgia or from the bacteriophage collection of the George Eliava Institute of Bacteriophage, Microbiology and Virology. In vitro screening of bacterial strains was performed by use of the spot-test method. The experiments were implemented three times by different groups of scientists.
  
  
  RESULTS
  The lytic activity of the commercial bacteriophage cocktails on the 41 E. coli strains varied between 66% (Pyo bacteriophage) and 93% (Enko bacteriophage). After bacteriophage adaptation of the Pyo bacteriophage cocktail, its lytic activity was increased from 66 to 93% and only one E. coli strain remained resistant. One bacteriophage of the Eliava collection could lyse all 9 K. pneumoniae strains.
  
  
  CONCLUSIONS
  Based on the high lytic activity and the potential of resistance optimization by direct adaption of bacteriophages as reported in this study, and in view of the continuing increase of antibiotic resistance worldwide, bacteriophage therapy is a promising treatment option for UTIs highly warranting randomized controlled trials.
authors.affiliation: Neuro-Urology, Spinal Cord Injury Center and Research, University of Zürich, Balgrist University Hospital Zürich, Switzerland.
authors.forename: Wilbert
authors.initials: W
authors.lastname: Sybesma
authors.affiliation: Institute of Medical Microbiology, University of Zürich Zürich, Switzerland.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Zbinden
authors.affiliation: The Eliava Institute of Bacteriophage, Microbiology, and Virology Tbilisi, Georgia.
authors.forename: Nino
authors.initials: N
authors.lastname: Chanishvili
authors.affiliation: The Eliava Institute of Bacteriophage, Microbiology, and Virology Tbilisi, Georgia.
authors.forename: Mzia
authors.initials: M
authors.lastname: Kutateladze
authors.affiliation: Tsulukidze National Center of Urology Tbilisi, Georgia.
authors.forename: Archil
authors.initials: A
authors.lastname: Chkhotua
authors.affiliation: Tsulukidze National Center of Urology Tbilisi, Georgia.
authors.forename: Aleksandre
authors.initials: A
authors.lastname: Ujmajuridze
authors.affiliation: Neuro-Urology, Spinal Cord Injury Center and Research, University of Zürich, Balgrist University Hospital Zürich, Switzerland.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Mehnert
authors.affiliation: Neuro-Urology, Spinal Cord Injury Center and Research, University of Zürich, Balgrist University Hospital Zürich, Switzerland.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Kessler
keywords: antibiotic resistance; antibiotics; bacteriophage adaptation; bacteriophages; urinary tract infection