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bioRxiv · 10.64898/2026.02.05.703977

Liquid-Infused Silicone Catheters Reduce Fungal Burden and Inflammation in Candidozyma auris Bladder Infections.

Abstract

Candidozyma auris is a high-priority, emerging fungal pathogen frequently isolated from urine in healthcare settings. These isolates are often associated with indwelling urinary catheters, a primary risk factor for catheter-associated urinary tract infections (CAUTIs). Despite its clinical prevalence, the mechanisms of C. auris colonization and pathogenesis within the bladder remain poorly understood. In this study, we screened C. auris isolates from diverse clades using an in vitro biofilm model and in vivo murine models of uncomplicated UTI and CAUTI. While in vitro biofilm formation varied among isolates, the presence of a catheter in vivo significantly enhanced fungal burden in the bladder. Notably, one strain (B11103) caused rapid systemic dissemination and mortality. To address this, we evaluated a liquid-infused silicone (LIS)-catheter coating, which has previously shown efficacy against other uropathogens. The LIS-coating significantly reduced C. auris attachment in vitro and, crucially, mitigated fungal burden on both the catheter and bladder tissue in vivo across all tested strains. For the hyper-virulent B11103 strain, LIS-catheters also significantly reduced dissemination to the kidneys and bloodstream. Furthermore, cytokine analysis revealed that C. auris CAUTI upregulates IL-6, CSF3, and CXCL1; notably, this damaging inflammatory response was dampened by the LIS-catheter. These findings demonstrate that catheterization potentiates C. auris pathogenicity and identify LIS-catheters as a promising, antimicrobial-sparing strategy to prevent colonization, systemic spread, and inflammation during C. auris CAUTI. IMPORTANCEThis research addresses the critical public health challenge posed by the emergence of Candidozyma auris, elucidating its pathogenesis in the urinary tract, the second most common yet understudied reservoir. Here, we find that C. auris exhibits plasticity in its ability to form biofilms in urine and cause uncomplicated UTIs and catheter-associated UTIs. Importantly, we show that our liquid-infused silicone (LIS)-catheters effectively disrupt this cycle by reducing fungal burden, preventing systemic spread, and dampening the damaging host inflammatory response. This work establishes the urinary tract as a critical niche for systemic entry and provides a validated strategy for infection prevention.

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BibTeXRIS

La Bella, A. A., Akegbe, H. L., Howell, C., Santiago-Tirado, F. H., Flores-Mireles, A. L.. 2026-02-05. Liquid-Infused Silicone Catheters Reduce Fungal Burden and Inflammation in Candidozyma auris Bladder Infections.. https://doi.org/10.64898/2026.02.05.703977

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