ILEAL CONDUIT STENOSIS - AN ENIGMA

Ileal conduit stenosis was diagnosed in 12 patients in the period 1981 -1994. The time between urinary diversion and this diagnosis was 7-30 (mean 14) years. The clinical picture, i.e. colicky flank pain and/or fever, was produced by upper urinary tract obstruction. Intravenous ur ography, loopography and looposcopy were used in diagnosis. Treatment consisted of removal of the conduit and replacement by a new ileal loo p or a continent reservoir, or partial resection with or without urete ric reimplantation. Light microscopy of the removed conduits showed se vere, sometimes transmural inflammation with submucosal fibrosis. Tran smission electron microscopy (TEM) demonstrated reduced height of micr ovilli, presence of glycocalyceal bodies and an increased number of ly sosomes. Other subcellular structures were intact. The pathogenesis of the stenosis is obscure. Microvascular insufficiency, infection in co njunction with exposure to urine, reaction to some noxious agent in th e urine or immunologic causation have been proposed. This late stenosi s seems to arise only when ileum is used as conduit. Its insidious cou rse calls for lifelong observation of the upper urinary tracts in thes e patients.