Monitoring of canine pancreas allograft function with measurements of urinary amylase.

A canine model of whole pancreas transplantation with pancreaticocystostomy was studied for predictability of graft rejection using urinary amylase (UA) monitoring. Six pancreatectomized dogs were transplanted without immunosuppression and with acute rejection occurring at a median of 9.5 days (range 7-12 days). A differential loss of allograft exocrine and endocrine function was demonstrated, with a gradual decrease in UA after transplantation but maintenance of fasting blood glucose levels (FBGL) till the day before complete loss of graft structure. Another 13 dogs treated with cyclosporin (25 mg/kg per day) had prolonged graft survival (P less than 0.01) with an actuarial median survival of 91 days (range 8-159 days). Five allografts were lost because of rejection and eight dogs died with functioning grafts. Fasting spot levels of UA less than 5000 iu/l or less than 10,000 iu/l had a positive predictivity of graft failure of 71% or 31%, respectively. Falls of UA levels of greater than 75% in 24 h and 48 h were seen equally in both rejecting and functioning allografts. This study confirmed the role of UA as an earlier marker of rejection than FBGL. The clinical role of UA will be important, but its use as a predictor of pancreas rejection may be dependent on a fall to a predetermined level rather than the rate of fall.