[Vascular complications after kidney transplantation].

INTRODUCTION: Despite high graft and recipient survival figures worldwide today, a variety of technical complications can threaten the transplant in the postoperative period. Vascular complications are commonly related to technical problems in establishing vascular continuity or to damage that occurs during donor nephrectomy or preservation [13].

AIM: The aim of the presenting study is to evaluate counts and rates of vascular complications after renal transplantation and to compare the outcome by donor type.

MATERIAL AND METHODS: A total of 463 kidneys (319 from living related donor--LD and 144 from cadaveric donor--CD) were transplanted during the period between June 1975 and December 1998 at the Urology & Nephrology Institute of Clinical Centre of Serbia in Belgrade. Average recipients' age was 33.7 years (15-54) in LD group and 39.8 (19-62) in CD group. Retrospectively, we analyzed medical records of all recipients. Statistical analysis is estimated using Hi-squared test and Fischer's test of exact probability.

RESULTS: Major vascular complications including vascular anastomosis thrombosis, internal iliac artery stenosis, internal iliac artery rupture, obliterant vasculitis and external iliac vein rupture were analyzed. In 25 recipients (5.4%) some of major vascular complications were detected. Among these cases, 22 of them were from CD group vs. three from LD group. Relative rate of these complications was higher in CD group vs. LD group (p < 0.0001). Among these complications dominant one was vascular anastomosis thrombosis which occurred in 18 recipients (17 from CD vs. one from LD). Of these recipients 16 from CD lost the graft, while the rest of two (one from each group) had lethal outcome.

DISCUSSION: Thrombosis of renal allograft vascular anastomosis site is the most severe complication following renal transplantation. In the literature, renal allograft thrombosis is reported with different incidence rates, from 0.5-4% [14, 15, 16]. Data from the present study demonstrate that the rate of this complication in LD group was low, only 0.3%, but significantly higher in CD group--11.8%. Many factors should be considered in order to understand for such significant difference among these groups. First of all, cadaveric transplant activity in our country is very low. In our series, median waiting period for renal transplantation was 2.8 years in LD group vs. 4.8 years in CD group (p < 0.01). Also, vascular damages because of long term hemodialysis are contributing factors. Mean age of CD recipients was 7.4 years bigger vs. LD recipients. Primary cadaveric graft damage by accident and further manipulations during cadaveric donor nephrectomy, preservation and perfusion are additional factors compromising the quality of cadaveric renal transplant outcome. Also, preoperative evaluation of cadaveric grafts is not as exact as in cases of LD grafts (excretory urography, arteriography, etc). In the available transplant literature it is almost impossible to find data about vascular complications by different donor types. Mostly, authors offer experiences related to all transplants and most of them agree that in the present time better results are obtained using living donors [17].