Abstract
PURPOSE: To assess long-term renal function and micturition pattern of males submitted to transurethral resection of the prostate (TURP) for moderate-to-severe lower urinary tract symptoms (LUTS) after renal transplantation (RT). To investigate the role of clinical and urodynamic (UD) parameters for bladder outlet obstruction (BOO) diagnosis in these patients. METHODS: Retrospective data analysis of ≥ 50 years old patients who underwent RT between 01/2005 and 12/2016. Patients with moderate-to-severe LUTS after RT who underwent a urologic evaluation and a UD study were included. TURP was performed in case of BOO diagnosis. Kidney function and micturition patterns were evaluated before, 3, 12, 24, 36, and 48 months after TURP. Predictors of BOO were assessed at univariable and multivariable logistic regression models. Statistical analysis was performed with STATA16. RESULTS: 233 male patients ≥ 50 years underwent RT. 71/233 (30%) patients developed voiding LUTS. 52/71 (73%) patients with moderate-to-severe LUTS underwent UD. TURP was performed in 36/52 (69%) patients, with BOO diagnosis. Median (interquartile range) follow-up was 108 (75-136) months. Maximum flow at flowmetry (Qmax), International Prostate Symptom Score and post-voided residual volume improved significantly after surgery. Serum creatinine decreased and glomerular filtration rate improved significantly at follow-up, especially when TURP was performed ≤ 6 months from RT. At the multivariable model, bladder capacity ≥ 300 mL (OR = 1.74, CI 95% 1.03-3.15, p = 0.043) and detrusor pressure at Qmax (OR = 2.05, CI 95% 1.48-3.02, p = 0.035) were the independent predictors of BOO. CONCLUSION: RT patients with moderate-to-severe LUTS at risk for BOO and graft failure are better identified by UD than clinical parameters. Bladder capacity and voiding pressure are key for the early diagnosis of BOO.