RECURRENT/DE NOVO MEMBRANOUS NEPHROPATHY AFTER RENAL TRANSPLANTATION: A REPORT FROM THE RENAL ALLOGRAFT DISEASE REGISTRY(RADR)

Abstract

586 Membranous nephropathy (MN) is an uncommon form of glomerulonephritis in renal allografts. This study illustrates the outcome of 16 cases of recurrent/de novo MN in renal allografts. A total of 4,967 renal transplants between six renal transplant centers (MCW, WU, UCSF, UW, UC, UL) were retrospectively analyzed for recurrent/de novo disease. A total of 16 cases(0.3%) of recurrent/de novo MN were identified in this population. Demographic patterns of the 16 were as follows: 14 males, 2 females, 10 white, 2 black, and 4 others. Their mean age was 41 yrs (range 25-56). Ten of 16 had cadaveric renal transplants. The native renal disease was known in 12 cases; 6 had MN; 3 had other forms of glomerulonephritis; and polycystic kidney disease, Alport's syndrome, and obstructive uropathy were seen in 1 each. MN was diagnosed by renal transplant biopsy after a mean period of 22 months (range 3-79 months). Renal biopsy was indicated through a combination of proteinuria and increased serum creatinine. There were 6 cases (37.5%) of recurrent MN and 10 (62.5%) de novo MN. In 68% of cases, the diagnosis was made within 2 years post-transplantation. The diagnosis of recurrence (n=6) occurred after a mean period of 15 months, and in de novo (n=10), 29 months post-transplantation (p=0.116). All patients were followed for a mean period of 62 months (range 18-115). During follow-up, eight (50%) of the patients lost their allografts. Actuarial kidney survival established by Kaplan-Meier for 1, 2, 3, 4 and 5 yrs was 94%, 87%, 73%, 54%, and 45%. Corresponding values for the remainder of the renal transplants were 85%, 81%, 78%, 72%, and 67% (Log-rank test, p<0.0001). The timing of recurrence did not differ in patients who experienced graft loss and those with a functioning graft (21 vs 24 months, p=0.796). The duration of follow-up after transplantation was similar in patients with and without graft loss (p=0.427). In conclusion, 1) 37.5% had recurrent MN, and 62.5% had de novo MN; 2) MN is associated with poor long-term graft survival (50% had lost their allografts); 3) in 2/3 of these cases, MN was diagnosed within 2 years post-transplantation; and 4) time to diagnosis was shorter in recurrence compared to de novo MN.