Therapeutic efficacy and short-term durability of trans-urethral amniotic bladder injections for the treatment of refractory COVID-associated cystitis.

Introduction: COVID-19-associated cystitis (CAC) may arise following a COVID-19 infection and is characterized by the development of novel or worsening overactive bladder (OAB). CAC is possibly associated with bladder mucosal damage and the release of pro-inflammatory cytokines, resulting in inflammation and fibrosis of the bladder wall. Amniotic membrane (AM) has been shown to possess anti-inflammatory and anti-fibrotic properties and might potentially be beneficial for CAC. This study investigated the safety and efficacy of bladder injections of AM in CAC patients with resistant OAB symptoms. Methods: Five CAC patients, with an average age of 73 ± 1.0 years and a median disease duration of 2.4 years, received intra-detrusor injections of 100 mg micronized AM under general anesthesia and were followed for 20 weeks. Key urodynamic measures (involuntary detrusor contraction and maximum cystometric capacity) were determined to evaluate treatment response. Quality of life (QOL) was assessed using the OAB assessment tool, and safety was analyzed. Results: All five patients showed improved urodynamic bladder function and significantly improved QOL improvements. The improvement was evident from 4 weeks post-treatment and sustained until 12 weeks. Symptoms re-surged at 20 weeks. No safety concerns arose during the study. Conclusion: The observed improvements in symptom scores and bladder volume parameters highlighted the promise of AM bladder injections as a viable intervention for CAC patients with refractory OAB symptoms. Comprehensive studies are needed to validate its therapeutic potential, and treatment protocol refinement is warranted to address the observed reduction in efficacy over time.