Endopyelotomy Failure Is Associated with Reduced Urinary Transforming Growth Factor- β 1 Levels in Patients with Upper Urinary Tract Obstruction

Abstract

Background and Purpose: We previously demonstrated that obstructed ureteropelvic junction (UPJ) segments from patients who had secondary pyeloplasty after endopyelotomy failure expressed transforming growth factor-β1 (TGF-β1) at levels significantly lower than patients who had primary pyeloplasty. In order to determine whether these differences in secreted TGF-β1 are detectable preoperatively in the urine, the TGF-β1 concentration of urine from patients undergoing endopyelotomy was determined and compared with that from subjects without urologic disease.Materials and Methods: Bladder and renal pelvic urine from the obstructed side was obtained from patients (N = 34) undergoing primary endopyelotomy for UPJ obstruction. Bladder urine was also obtained from sexand age-matched patients (N = 26) having no evidence of urinary tract obstruction. The TGF-β1 concentration was determined by ELISA and normalized to the creatinine concentration. Results: The bladder urine TGF-β1 concentration was significantly (P < 0.02) higher in patients with UPJ obstruction (86.1 ± 20.5 pg/mg of creatinine) than in those without obstruction(29.7 ± 8.0 pg/mg creatinine). The TGF-β1 concentration in the bladder urine of patients who underwent endopyelotomy and later returned because of UPJ obstruction (25.7 ± 12.3 pg/mg of creatinine; N = 6) was not significantly different from the value in unobstructed patients but was significantly lower (P < 0.01) than in patients for whom endopyelotomy was successful(100 ± 24.29 pg/mg of creatinine; N = 28). The renal pelvic urinary TGF-β1 concentration was higher in patients for whom endopyelotomy was successful (772 ± 490.1 pg/mg of creatinine) than in patients who underwent endopyelotomy and later returned because of UPJ obstruction (126.1 ± 41.9 pg/mg of creatinine). Conclusions: These data suggest that preoperative concentration of TGF-β1 in the bladder urine of patients with UPJ obstruction who fail endopyelotomy is not significantly different from that in subjects with no urologic disease and significantly lower than in those patients for whom endopyelotomy is successful. Thus, the preoperative bladder urine concentration of TGF-β1 may assist in selecting patients for this operation, although further investigation is necessary.