ROUTINE EARLY BIOPSY OF ALLOGRAFTS WITH DELAYED FUNCTION - CORRELATION OF HISTOPATHOLOGY AND TRANSPLANT OUTCOME

Approximately 25-30% of our cadaveric renal transplant recipients have required post-transplant dialysis. In an attempt to discern the etiol ogy, routine biopsies were performed 7-10 d post-transplant and repeat ed weekly. All patients received a triple-therapy cyclosporine-based r egimen with (N=61) or without (N=10) antilymphocyte induction. Rejecti on was classified as 'early' when it appeared on the first biopsy (8.9 +/-0.3 d), 'delayed' when it appeared only on the second biopsy (17.9/-1.0 d) and persistent when present on both biopsies. Adequate biopsy material was obtained from 71 patients who provided a total of 117 bi opsies. Acute tubular necrosis was the most common finding (50%) in th e first biopsy, while rejection occured in 30% of biopsies, Rejection on the first biopsy was strongly associated with primary nonfunction ( PNF) (8 of 21 vs. 1 of 40, p less than or equal to 0.0001). In contras t, eight patients without rejection on Biopsy 1 developed delayed reje ction on Biopsy 2; only one was associated with PNF. DGF persisted bey ond the second week in 38 patients; 17 (38%) of which had rejection. N ine patients had persistent rejection 55% of whom experienced PNF comp ared to 6% without persistent rejection (p less than or equal to 0.001 ). The occurrence of early rejection was associated with pretransplant peak PRA levels >50% (p less than or equal to 0.01). Graft survival f or all patients was 79% and 65% at 1 and 2 yr, Rejection influenced 1- yr graft survival for patients with persistent rejection who had 55% i ncidence of primary nonfunction and 1- and 2- yr graft survival rates of 42% and 37%. These data indicate that early biopsies are useful in unmasking rejection during DGF and at predicting primary nonfunction. Based on these data we recommend the routine utilization of biopsies f or all patients with DGF.