Renal function in the setting of urinary diversion

Incorporating bowel into the urinary tract sets the stage for a potentially dangerous situation for the upper part of this tract. Obstruction, reflux and chronic bacteriuria may develop, all of which can all be detrimental. Most reports on renal function have used IVP and serum creatinine only, methods which are inadequate for proper assessment. Long-term follow-up of patients with ileal conduit diversion reveals a high incidence of morphological and/or functional damage to the kidneys. Refluxing techniques for implanting the ureters have usually been employed. In patients with continent cutaneous diversion or orthotopic bladder substitution, some recent publications have shown rather well preserved glomerular filtration rates. Traditionally, antirefluxing ureteric implantation has been used in these patients. There is presently a trend towards refluxing anastomosis in this setting, providing a low pressure pouch has been constructed. However, pressure can be high in such pouches and bacteriuria is common. The consequences for the fate of the upper urinary tract is unknown and caution should be exercised in recommending such techniques. There is clearly a need for prospective randomized controlled studies on the issue of refluxing versus antirefluxing anastomosis in continent urinary reconstruction. Patients with continent or non-continent diversion should have lifelong follow-up with regard to the upper urinary tract.