Role of extended spectrum beta lactamases producing E. coli and Acanthamoeba in urinary tract infections

About 150 million cases of Urinary Tract Infections (UTIs) happen annually worldwide costing the NHS billions of pounds. Antibiotic resistance caused by Extended-Spectrum β-lactamases (ESBLs) producing organisms, particularly E. coli, have become an increasing problem, and recurrent infections are not uncommon. It has been confirmed that pathogenic bacteria survive and multiply inside the protozoan parasite, Acanthamoeba. The indiscriminate use of various antimicrobial drugs has resulted in the development of drug resistance. Therefore, looking for new or additional antimicrobial compounds is urgent. Four clinical strains of E. coli (three ESBL+ve (TEM, AmpC, and OXA-48) and one ESBL–ve used as a control) were used in this project to study the interaction of the above microorganisms with the urinary tract and their possible alternative treatment. All strains were characterised by PCR and sensitivity testing. Results showed that all ESBL producers were sensitive to Ciprofloxacin. OXA-48 displayed an increased resistance when compared with other strains. The 2-D gel electrophoresis was used to further identify the microorganisms and results showed many proteins were featured in OXA-48 compared with others. All uropathogens exhibited the ability to associate with and invade Acanthamoeba T4 and the urothelial cell line (TRET-NHUC). However, OXA-48 was the only one survived and multiplied inside both Acanthamoeba and the cell line. This project has confirmed that cytotoxicity relies on the number of intracellular bacteria. Furthermore, the cytotoxic effect of bacterial conditioned medium was higher than live and heat-killed bacteria. This study also investigated the antimicrobial efficacy of cetylypyridinium chloride (CPC). An increased concentration of CPC has a positive correlation with the inhibition of bacteria. To confirm the presence of Acanthamoeba in urine, 76 samples were collected from patients with ESBL+ve bacteria. It is interesting to report that more than 17% of urine samples were positive for Acanthamoeba supporting our hypothesis that the amoeba may play a role in UTIs.