Urethral Instability and Overactive Bladder Symptoms: Evidence From Clinical Practice.

Urethral instability (URI) is characterized by spontaneous fluctuations in resting urethral pressure, typically observed during the bladder filling phase in the absence of detrusor contractions. Despite decades of reports, URI remains under-recognized in clinical practice and absent from international guidelines. Some patients with refractory lower urinary tract symptoms (LUTS) may have underlying URI not identified by standard assessments focused on detrusor overactivity. This article presents three cases of patients with refractory LUTS, where urodynamic studies, including urethral profilometry, revealed urethral pressure instability associated with LUTS. The studies were conducted according to ICS (International Continence Society) standards. The findings support a potential pathophysiological role for the urethra in LUTS, independent of detrusor function. Recognition of URI may inform alternative therapeutic approaches, such as neuromodulation. Despite promising data, the lack of standardized definitions and methodologies hampers clinical implementation. URI may represent a distinct functional entity contributing to OAB symptoms. Incorporating urethral pressure assessment in urodynamics, especially in refractory cases, is essential to optimize diagnosis and treatment.