Uretero-neocystostomy in a swine model of kidney transplantation: A new technique

Abstract

Swine constitute a well-characterized large animal model for kidney transplantation (K-Tx) although the uretero-neocystostomy represents a crucial aspect because of the very small caliber of the ureter and the mucosal susceptibility to the edema during surgical management. Besides infectious and occlusive complications limited the employment of a stent and the peculiar anatomy of the species prevents its removal without an operative approach. These features find an equivalent in children (<4 year old) candidates to urological surgery. We investigated an uretero-neocystostomy technique to be applied in case of narrow caliber without using endoluminal device. Thirty unrelated large-white piglets, divided into three equal groups (n = 10) on the basis of the uretero-neocystostomy technique used, underwent K-Tx while receiving a double immunosuppressive regimen. We developed a direct uretero-neocystostomy (Direct) technique and compare this with the gold standard Lich-Gregoir (LG) and Leadbetter-Politano (LP) techniques. After 60 days, the ureteral complication rates were: group 1 (LG): 60% (6/10, three early and three late strictures); group 2 (LP): 40% (4/10, two leakages, one early stricture, and one isolated ureteral dilatation); group 3 (Direct): 10% (1/10, one isolated ureteral dilatation). No bacterial cystitis or nephritis occurred; retrograde cystograms were negative for refluxes in every group. The comparison between the old techniques and the new one (LG and LP versus Direct) showed a lower incidence of complications among the animals that underwent the new direct technique (P < 0.05). This technique could be applied clinically in selected pediatric cases either of transplantation or reflux.