Introduction Research has previously described the presence of intracellular bacterial communities (IBCs) caused by uropathogenic E.coli (UPEC) in paediatric patients. However, its pathogenetic implications and immunologic/ inflammatory profiling has seldom been reported or adequately discussed. Here we present the case of a 14-year-old female with constant UPEC UTIs for six years, necessitating multiple rounds of antibiotics. We aimed to identify the long-term presence of IBCs in the patient’s urothelial cells and understand its relevance to localized inflammation.
Methods: Mid-stream urines were collected at 3-month intervals, alongside her first cystoscopy results. Exfoliated urothelial cells were stained with E.coli, LAMP1, UPIIIa, WGA and DAPI. Samples were captured as z-stacks on the Marianas Multimodel super resolution confocal microscope. Flow cytometry was used to identify urinary immune populations. Cytokines were quantified using commercially available ELISA kits.
Results: Over a six-month symptomatic period of active antimicrobial therapy, urothelial cells from Patient X displayed the extensive constant presence of IBCs in urothelial cells. >60% of cells were infected at any given point, with no significant differences between each sample. A large population of non-urothelial cells were also positive for IBCs, including CD45+ and MR1+ populations. Significant changes (p<0.001) in TNF-a, IL-1b, IL-6 and IL-8 concentrations and extensive pyuria also indicated a consistently inflamed bladder.
Conclusion: This study for the first time proves the long-term extensive presence of UPEC IBCs in a chronic UTI patient despite intensive antibiotic therapy. The patient presents with a constant localized inflammatory condition, possibly due to IBC presence. This study provides a pertinent reminder that long term antibiotics cannot eradicate IBCs. Future investigations will assess the relationship between IBC phenotype and localized inflammation.