Bacteriophage therapy for Escherichia coli-induced urinary tract infection in rats
Abstract
Background: The present study evaluates the efficacy of bacteriophage therapy for urinary tract infection (UTI) in rats. Methods: UTI was established by inoculating Escherichia coli (100 μl) at a concentration of 1.5 × 108 CFU/ml per urethra via a cannula in different groups of rats. For treatment, phage cocktails (200 μl) were administered at varying concentrations of 1 × 108 PFU/ml, 1 × 107 PFU/ml and 1 × 106 PFU/ml. Results: The two doses of phage cocktail at the first two concentrations resulted in the cure of UTI. However, the lowest concentration of the phage cocktail warranted more doses to eradicate the causative bacteria. Conclusion: The quantity, frequency and safety of doses could be optimized in a rodent model using the urethral route.
Plain language summary
Antimicrobial resistance is primarily caused by antibiotic overuse and misuse, which results in a decline in the ability of antibiotics to treat infections. Urinary tract infections (UTIs) are common but difficult to treat, as they are frequently caused by multidrug-resistant bacteria. Escherichia coli is a common cause of UTIs. Bacteriophages are a potentially viable alternative for the treatment of bacterial infections, and despite the numerous benefits of using phages as antibacterial therapeutics, there are surprisingly few original research articles based on clinical trials, specifically against UTIs. In this study, the efficiency of a customized bacteriophage cocktail for the treatment of UTIs, with varied doses administered directly into the urinary bladder of rats, was evaluated. At higher concentrations, UTIs were completely eradicated after two doses of the bacteriophage cocktail. However, at lower concentrations, additional doses were required to eradicate the infection. Phage therapy appears to have therapeutic potential, and this study indicates the potential frequency of dosages at appropriate concentrations. Phage therapy was both effective and safe.
Papers of special note have been highlighted as: • of interest
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