HLA-identical sibling renal transplantation - a 21-yr single-center experience

Human lymphocyte antigen (HLA)-identical sibling organs offer the best long -term outcomes for recipients of a renal transplant apart from an identical twin. Unlike cadaveric transplants, however, factors that affect long-term survival of these immunologically privileged grafts are not well described . We reviewed 108 HLA-identical transplants performed at our institution betw een January 1977 and February 1993. Variables chosen for graft survival ana lysis were: gender, age and ABO blood type of donors and recipients, panel reactivity antibodies (PRA), blood transfusions prior to transplant, pregna ncies, and the underlying renal disease. Additionally, incidence of acute r ejection (AR), timing of AR, serum creatinine levels at 1 wk and at 1 yr, a nd presence of hypertension were included in the analysis. Mean follow-up w as 130.9 +/- 58.2 months (range 38-250 months). Actual 5-yr patient and gra ft survivals were 92 and 88%, respectively. Thirty-eight grafts were lost, and 22 recipients died during the observation period. Death was the main ca use of graft failure. Cardiac events accounted for the majority of deaths. AR occurred in 46% and repeated rejections in 11% of recipients. Actuarial graft survival at 10 yr was poorer for patients with any AR (69%), and sign ificantly worse with repeated AR (33%), compared to patients without AR (86 %, p = 0.001), Sixty percent of all rejections and 88% of the first rejecti ons occurred in the first 60 d post-transplantation. The first AR that occu rred after 60 d was associated with poor graft survival (49 vs. 70%, p = 0. 04). Recipients with renal diseases with potential to recur (membranous glo merulonephritis (MGN), membrano-proliferative glomerulonephritis (MPGN), fo cal and segmental glomerulonephritis (FSGN), polyarteritis nodosa (PAN), ra pid progressive glomerulonephritis (RPGN), Henoch-Schoenlein purpura (HSP), diabetes mellitus (DM), interstitial nephritis, systemic lupus erythematos us (SLE) and chronic glomerulonephritis (CGN)) faired worse as a group than recipients with hypertensive nephrosclerosis (HTN), autosomal dominant pol ycystic kidney disease (ADPKD), Alport's, reflux or congenital dysplasia (6 8 vs. 96% at 10 yr, p = 0.0009). Poor patient survival was seen in diabetic s (71 vs. 88% at 10 yr, p = 0.01). There was a trend to poorer graft surviv al in diabetic recipients when compared to non-diabetics (65 vs. 81% at 10 yr, p = 0.054), Elevated creatinine at 1 yr was associated with worse graft survival. Likewise, the magnitude of creatinine increase during the first year directly correlated with the risk of graft loss. Hypertensive patients were more likely to lose their grafts than normotensive recipients (72 vs. 86%, p = 0.04). Pre-transplant blood transfusion, pregnancy, and PRA level were not associated with increased graft failure or AR. Graft survival was not affected by gender, age, or ABO blood type of donors or recipients. In conclusion, better prevention and treatment of AR, hypertension, and car diac disease should improve graft and patient survival. Close attention to recurrence of disease and subtle changes in the creatinine level during the first year might dictate early diagnostic and, hopefully, therapeutic inte rventions.