Repurposing the drug duloxetine for its antibacterial activity against catheter associated urinary tract infections

Catheter associated urinary tract infection is an important nosocomial infection that can be involved by one or more parts of the urinary system including bladder, ureters, urethra and kidneys. The infection is common as studies estimated that the mean incidence of catheter associated urinary tract infection per 1000 catheter-days was as high as 9.86, and when the infection is caused by multidrug resistant bacteria, it can lead to severe sufferings to the patients with longer morbidity and higher medical expenses. Many of the catheter associated urinary tract infection causing bacteria are known to form biofilms and pathogens like Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Enterococcus faecalis etc. are among the most notorious. As such biofilms are extremely resistant to ant external physical, chemical or biological agents, the treatment against them pose serious challenges. Present study analyses the antibacterial activity of a repurposing anti-depression drug duloxetine against two of the most prevalent catheter associated urinary tract infection causing bacterial pathogens – viz. Escherichia coli and Enterococcus faecalis. Duloxetine showed antibacterial and the lowest inhibitory concentration was found to be 37.5 µg/ml for both microbes. It was also evaluated for their effect against microbial colonization and biofilm formation. The duloxetine didn’t allow the microbial colorization up to its minimum inhibitory concentration thus the biofilm reduction was observed as 64% and 86% for Escherichia coli and Enterococcus faecalis respectively. To prevent biofilm formation on urinary catheters, the drug was coated with silicone catheter tube and exhibited antibacterial activity against Escherichia coli and Enterococcus faecalis. Study suggested that duloxetine can be an effective antibacterial agent against Escherichia coli and Enterococcus faecalis.