Recurrence of IgA nephropathy among renal allograft recipients from living donors is greater among those with zero HLA mismatches.
BACKGROUND
Risk factors contributing to recurrence of IgA nephropathy (IgAN) after transplantation are unclear. Some (but not all) series have suggested greater degrees of human leukocyte antigen (HLA) matching play a role.


METHODS
Using registry data including all kidney transplants performed in Australia and New Zealand between 1987 and 2004 we examined IgAN recurrence among living donors with zero HLA-mismatches.


RESULTS
Of 1354 grafts performed in recipients with IgAN, live donors (LDs) accounted for 488 including 108 with zero HLA-mismatches. Biopsy-proven IgAN recurrence was reported for 110 (7%) of grafts overall, but 17% of those who received zero HLA-mismatched LD grafts (HR for recurrence free graft survival 2.7 [95% CI 1.5-5.1], P=0.001). There was no significant difference in recurrence rates between zero and >or=1 HLA-mismatched grafts from cadaveric donors (CDs). Recurrence of IgAN was associated with worse graft survival, more so among LD recipients (HR 8.5 [4.8-15.2], P<0.001) than CD recipients (HR 4.5 [2.6-7.5], P<0.001). However, there was no difference in graft survival between zero and >or=1 HLA mismatched LD recipients whose native disease was IgAN. In contrast, zero HLA mismatched recipients of kidneys with other primary renal disease enjoyed a graft survival advantage. No difference in recurrence rates was seen among those with HLA B12, B35 or DR4.


CONCLUSIONS
The increased rates of IgAN-related graft loss among zero HLA-mismatched LD recipients counterbalance the advantage normally seen among zero HLA-mismatched recipients. However, since graft survivals are similar, there is no reason to avoid donor-recipient pairs with zero HLA-mismatches in this setting.
McDonald
Stephen P
SP
ANZDATA Registry, Adelaide, Australia. stephenm@anzdata.org.au
Russ
Graeme R
GR
D001315:Australia / Q000453:epidemiology; D005260:Female; D005922:Glomerulonephritis, IGA / Q000453:epidemiology* / Q000276:immunology; D006085:Graft Survival; D006650:Histocompatibility Testing; D006801:Humans; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D014184:Transplantation, Homologous; D016896:Treatment Outcome