A 20-YEAR EXPERIENCE WITH ILEAL CONDUIT URINARY DIVERSION : Late Complications and Ileal Loop Function

A series of 234 patients treated by ileal conduit urinary diversion in the past 20 years were reviewed. Diversion was carried out for malignant diseases in 228 patients. The average followup period was 4 years. Patients were followed with periodic excretory urography (IVP) and loopograms. Preoperative and postoperative IVPs were compared to assess the effect of time on renal function and structure. IVPs taken 3 months after the urinary diversion in 190 patients disclosed pyelographic deterioration in nearly 15%, whereas only 89% of the cases were estimated to have developed further deterioration in the long term follow up (4 years or longer). The levels of intrinsic creatinine clearance which were measured at two different terms (1980, 1983) did not significantly change in 16 patients who were followed for over 6 months. Stone formation was a common late complication associated with significant long-term deterioration in either renal function or pyelographic appearance. The incidence of stone formation was 10.2% in 176 patients who were followed up for over 6 months. Complete laboratory examinations in these patients disclosed no metabolic abnormalities such as hyperchloremic acidosis and hypercalciuria. Surgery was necessary in 9 patients and all the stones extracted were composed of magnesium ammonium phosphate. In 17 out of the 18 stone formers, neither stomal stricture nor ureteroileal stenosis was identified. To evaluate the function of the ileal loop, myoelectric activities were measured from the conduit stoma in 6 patients with, normal pyelographic appearance and in 4 patients who developed stones. This examination revealed a significantly decreased response of the ileal loop to furosemide administration in the latter (Group II), as compared to the former (Group I). The ileal conduit dysfunction estimated by this method was thought to be a major risk factor involved in the stone formation.