SIMULTANEOUS PANCREAS AND KIDNEY-TRANSPLANT REJECTION - SEPARATE OR SYNCHRONOUS EVENTS

The results of simultaneous pancreas and kidney transplantation (SPK) cannot be matched by pancreas transplantation alone (PTA), in part bec ause an independent diagnosis of pancreas graft rejection remains diff icult. The relationship between rejection of the pancreas and rejectio n of the kidney is poorly understood, and it is not known whether simu ltaneous transplantation of both organs confers true protection to eit her graft. To study these questions, reliable canine allotransplant mo dels of kidney transplantation alone (KTA), PTA, and SPK were establis hed, Sixty-seven mongrel dogs received KTA (n=21), PTA (n=23), or SPH (n=23) with either no immunosuppression, low-dose cyclosporine (CsA)-b ased immunosuppression, or high-dose CsA-based immunosuppression. Need le core biopsy (NCB) and fine needle aspiration biopsy (FNAB) were per formed at 0, 2, 4, 7, 9, 11, 14, 21, and 30 days or at the time of gra ft failure. Pancreas and kidney graft survival after SPK; was signific antly shorter in dogs given low-dose CsA than in dogs given high-dose CsA (pancreas, P<0.04; kidney, P<0.03). Concurrent NCBs and FNABs were performed on 227 occasions in pancreas grafts and 229 occasions in ki dney grafts. The time to initial evidence of rejection by NCB was not different in any immunosuppressed group. Synchronous rejection occurre d in 73% of immunosuppressed SPK: biopsies. Kidney-only rejection occu rred in 23% of biopsies and pancreas-only rejection occurred in only 3 % after SPK, All markers of pancreas graft rejection were poor, with t he most sensitive being NCB of the simultaneously transplanted kidney, In summary, recipients of SPK required more immunosuppression than re cipients of PTA, and improved PTA survival should be achievable with m ore sensitive markers of rejection. Markers of kidney rejection were t he most sensitive indicators of pancreas rejection, and independent pa ncreas rejection was uncommon after SPK.