[Frontiers in Bioscience 2, e34-40, August 1, 1997]|
PANCREAS TRANSPLANTATION: INDICATIONS, CLINICAL MANAGEMENT, AND OUTCOMES
John P. Leone, MD, PhD1, Abhinav Humar1 , Rainer W. G. Gruessner, MD, PhD2, and David E.R. Sutherland, MD3
1Transplant Fellow, Department of Surgery, University of Minnesota, Minneapolis, Minnesota, 2Professor & Chief, Section of Pancreatic Transplantation, Department of Surgery University of Minnesota, Minneapolis, Minnesota, 3Professor & Chief, Division of Transplantation, Department of Surgery, University of Minnesota, Minneapolis, Minnesota
Received 6/15/97; Accepted 6/23/97; On-line 7/25/97
6. IMMUNOSUPPRESSION & MONITORING
The introduction of bladder drainage into the recipient procedure has a two-fold advantage. First, the technique allows for safe, effective drainage of exocrine secretions. Second, it also allows for monitoring of graft function, and therefore, rejection (14). Urinary amylase can be monitored and a rejection episode suspected when amylase levels fall by at least 50% (15,16). Additionally, a rise in serum pancreatic enzymes often precedes or occurs concordantly with falling urinary amylase levels (17,18). However, elevated serum enzymes can be a reflection of graft pancreatitis, possibly due to urinary reflux, and thus, a biopsy diagnosis may be required (see below). Rising serum enzymes should first be managed by relieving intra-bladder, urinary pressures; accomplished by placement of a urethral catheter.
For recipients of simultaneous pancreas/kidney transplants, serum creatinine levels remain the most sensitive marker for rejection. Rarely, a discrepancy in rejection of either the kidney or pancreas graft occurs. This situation requires close monitoring of serum creatinine and urinary amylase levels. Both markers are followed until function of the grafts stabilize. In cases of pancreas alone recipients, declining urinary amylase levels and/or rising serum amylase levels are the only indicators of graft rejection and a biopsy is usually required to confirm the diagnosis. To obtain a biopsy specimen, cystoscopic transduodenal or CT guided approaches are available (19-22). These procedures have been found to be both safe and reliable.
During the early years of transplantation, immunosuppression consisted of a steroid combined with azathioprine. However, a new era began with the introduction and wide-spread use of cyclosporin during the 1980's. Since that time a few additional agents have become part of the armentarium in the fight against rejection. Most centers now use quadruple therapy consisting of an inducing agent given at the time of transplantation (usually an anti-lymphocyte gammaglobulin) followed by maintenance immunosuppression of azathioprine or mycophenolate mofetile, cyclosporin or tacrolimus, and a tapering dose of steroids (23,24). The development of new immunosuppressive agents is a field filled with exciting potential and may soon bring forth compounds which will eliminate the need for some of the existing drugs and thus eliminate many of their hazardous side-effects.