Two-phase Intravesical Injection of Apheresis-derived Platelet-rich Plasma for Non-ulcerative Primary Bladder Pain...

To prospectively evaluate the efficacy and predictive factors of a 2-phase intravesical injection protocol using apheresis-derived platelet-rich plasma (PRP) in patients with refractory non-ulcerative primary bladder pain syndrome (PBPS).

Between June 2023 and August 2025, 102 patients with PBPS were stratified into Groups A, B, and C based on cystoscopic grading of hydrodistention (Grade I-III). All patients underwent video-urodynamic studies and PRP collection, followed by a 2-phase intravesical injection protocol comprising an intensive weekly phase for three weeks and a consolidation monthly phase for three months. Follow-up assessments were conducted at baseline, 1 month, and 6 months after the treatment. Outcome measures included Global Response Assessment, questionnaire scores and voiding diary.

Compared with baseline, all groups demonstrated significant improvements in questionnaire scores and voiding diary at 1 month post-treatment, with Groups B and C showing significantly greater improvement than Group A in most of these. At 6 months post-treatment, only Groups B and C maintained significant improvements in all aforementioned parameters. Consistently, the treatment success rate was significantly lower in Group A than in Groups B and C at follow-up. Nine patients (9.4%) experienced self-limiting gross hematuria, and no other adverse events were reported. Maximal bladder capacity and cystoscopic grade were associated with 1-month post-treatment efficacy. However, only cystoscopic grade was independently predictive factor.

Two-phase intravesical injection of autologous apheresis-derived PRP is a safe and effective treatment for refractory non-ulcerative PBPS. Cystoscopic grading of hydrodistention serves as an independent predictor of treatment response.