Murine models describe a defined host/pathogen interaction for urinary tract infection, but human cell studies are scant. Although recent human urothelial organoid models are promising, none demonstrate long-term tolerance to urine, the natural substrate of the tissue and of the uropathogens that live there. We developed a novel human organoid from progenitor cells which demonstrates key structural hallmarks and biomarkers of the urothelium. After three weeks of transwell culture with 100% urine at the apical interface, the organoid stratified into multiple layers. The apical surface differentiated into enlarged and flattened umbrella-like cells bearing characteristic tight junctions, structures resembling asymmetric unit membrane plaques, and a glycosaminoglycan layer. The apical cells also expressed cytokeratin-20, a spatial feature of the mammalian urothelium. Urine itself was necessary for full development, and undifferentiated cells were urine-tolerant despite the lack of membrane plaques and a glycosaminoglycan layer. Infection with Enterococcus faecalis revealed the expected invasive outcome, including urothelial sloughing and the formation of intracellular colonies similar to those previously observed in patient cells. This new biomimetic model could help illuminate invasive behaviours of uropathogens, and serve as a reproducible test bed for disease formation, treatment and resolution in patients.

Chronic increases in leptin concentration may enhance the growth of colonic cancers via MAPK and PI3-K pathways. These effects of leptin could provide a link between obesity and colonic cancer, and may represent a target for anticancer drug development.

Purpose To measure the effects of an unplanned, sudden cessation of treatment in an unselected group of patients with chronic painful LUTS managed with protracted antimicrobial treatment and to report these observational data collected from a cross-over process. Materials and methods The imposition of a guideline resulted in the immediate cessation of antibiotic treatment in a cohort of patients with chronic painful LUTS and microscopic pyuria. Patients were assessed before treatment withdrawal, whilst off treatment, and following reinstatement. Outcome measures included a validated symptom score, microscopic enumeration of urinary white cells and uroepithelial cells, and routine urine culture. Results These patients had reported treatment-resistant, painful LUTS for a mean of 6.5 years before treatment at this centre. Treatment was stopped in 221 patients (female = 210; male = 11; mean age = 56 years; SD = 17.81). Sixty-six per cent of women were post-menopausal. After unplanned treatment cessation, 199 patients (90%; female = 188; male = 9) reported deterioration. Eleven patients required hospital care in association with disease recurrence, including acute urinary tract infection (UTI) and urosepsis. Symptom scores increased after cessation and recovered on reinitiating treatment (F = 33; df = 2; p < 0.001). Urinary leucocyte (F = 3.7; df = 2; p = 0.026) and urothelial cells counts mirrored symptomatic changes (F = 6.0; df = 2; p = 0.003). Routine urine culture results did not reflect changes in disease status. Conclusion These data support the hypothesis that treating painful LUTS associated with pyuria with long-term antimicrobial courses, despite negative urine culture, is effective. The microscopy of fresh unspun, unstained urine to count white cells and epithelial cells offers a valid method of monitoring disease. An unplanned cessation of antibiotic therapy produced a resurgence of symptoms and lower urinary tract inflammation in patients with chronic LUTS, supporting an infective aetiology below the level of routine detection.

A significant proportion of urinary tract infection (UTI) patients experience recurrent episodes, due to deep tissue infection and treatment-resistant bacterial reservoirs. Direct bladder instillation of antibiotics has proved disappointing in treating UTI, likely due to the failure of infused antibiotics to penetrate the bladder epithelium and accumulate to high enough levels to kill intracellular bacteria. This work investigates the use of nitrofurantoin loaded poly(lactic-co-glycolic acid) (PLGA) particles to improve delivery to intracellular targets for the treatment of chronic UTI. Using electrohydrodynamic atomisation, we produced particles with an average diameter of 2.8 µm. In broth culture experiments, the biodegradable particles were effective against a number of UTI-relevant bacterial strains. Dye-loaded particles demonstrated that intracellular delivery was achieved in all cells in 2D cultures of a human bladder epithelial progenitor cell line in a dose-dependent manner, achieving far higher efficiency and concentration than equivalent quantities of free drug. Time-lapse video microscopy confirmed that delivery occurred within 30 minutes of administration, to 100% of cells. Moreover, the particles were able to deliver the drug to cells through multiple layers of a 3D human bladder organoid model causing minimal cell toxicity, displaying superior killing of bacterial reservoirs harboured within bladder cells compared with unencapsulated drug. The particles were also able to kill bacterial biofilms more effectively than the free drug. These results illustrate the potential for using antibiotic-loaded microparticles to effectively treat chronic UTIs. Such a delivery method could be extrapolated to other clinical indications where robust intracellular delivery is required, such as oncology and gene therapy.

Key content Up to one‐third of healthcare personnel still have concerns about speaking up when they notice potential errors. Cultivation of a shallow authority gradient encourages trainees to clarify instructions, challenge decisions and voice concerns, thereby reducing ambiguity and potential errors. Senior doctors should support junior team members who raise concerns by encouraging a working environment that is effective and safe. Aviation, rail and maritime industries recognise that steep authority gradients can lead to reluctance to escalate, resulting in near misses and fatalities. Learning objectives To understand the difference between hierarchy and authority gradient. To learn how graded assertiveness techniques such as ‘advocacy and inquiry’, PACE and CUSS can be used as non‐confrontational tools to speak up. To understand that senior doctors should practise active listening and have insight into their own openness when challenged.