[Renal graft survival in patients with systemic lupus erythematosus]

End-stage renal disease is an important cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). In 1975, the US Renal Transplant Registry reported the first lupus patients, who received a renal transplant. This study reported 60% and 55% patient/graft survival respectively at a mean time of two years; these results were similar to those of non-lupus transplanted patients in this same post-transplant lapse time. Renal transplantation is a world wide accepted therapeutic option in the treatment of SLE patients.

In order to identify the risk factors associated to renal graft loss in SLE patients and to compare graft survival between these patients and control transplant patients, matched by age, gender, haplotype match, and transplant date (+/- three years), we performed a retrospective analysis of all SLE patients that received a renal transplant in our Institute.

From 1967 to March 1997, 25 (5.5%) out of 452 renal transplants were performed in 22 SLE patients, mean age 29 +/- 10 years, 20 were female (90%). In 18 patients (85.7%) we obtained pre-transplant histological diagnosis: 13 (72%) type IV glomerulonephritis according to the OMS classification, three (17%) type VI, and two (11%) type III. Twelve patients (57%) were subjected to hemodialysis in the pre-transplant period and none (43%) to peritoneal dialysis. The time elapsed between the diagnosis of SLE and the start of dialysis was 50 +/- 70 months, the time on dialysis was 18 +/- 17 months, the post-transplant renal follow-up 46.9 +/- 41.5 months, and the graft source: 18 (78%) from living related (three sharing 0 haplotypes, 12 sharing 1 haplotype, and three sharing 2 haplotypes), and five (22%) from cadaver donors. Triple drug immunosuppresive therapy (cyclosporine, azathioprine, and prednisone) was employed in 17 patients and double drug therapy (azathioprine and prednisone) in the remaining six cases. We registered seven acute rejection episodes in five patients (30%), one of them lost the graft. Five patients presented a post-transplant thrombotic event, two of these were in the graft's artery. In two patients post-transplant SLE activity was documented, one case in with renal activity in the graft and the other with extrarenal activity. Risk factors analyzed for graft loss: number of pre-transplant thrombosis events, time elapsed between diagnosis of SLE at start of dialysis (< or = 6 months), time on dialysis (< or = 12 months), graft source, chronic rejection, and follow-up were not significant; in contrast, post-transplant thrombosis was the only identified risk factor for graft loss. Graft survival analysis at 50 months in SLE transplanted patients versus control non-SLE transplanted patients did not show significant differences (74% vs. 83%, log rank 0.11).

Post-transplant thrombosis was identified as a risk factor for graft loss. In concordance with recent studies, pre-transplant thrombosis, time elapsed between diagnosis of SLE at start of dialysis and time on dialysis were not risk factors for graft loss in this study. Graft survival in renal transplants recipients with SLE was not different from that of the general renal transplant population.