**9.2. Diabetes relapse**

Not least important, patients should be advised to maintain a proper diet to avoid weight gain, promote physical activity, avoid sun exposure, prohibit or limit the consumption of alcohol and smoking, recommend suitable footwear to avoid chafing and periodic podiatric check-up, and, in women of childbearing age, recommend measures of contraception to avoid

The incidence of acute rejection is higher in pancreas transplant than those reported in kidney transplantation. The actual incidence must be individualized according to transplant modality, recipient immunological risk, induction and maintenance immunosuppression, and

Overall 1-year rejection incidence varies between 14.7% [34] and 21% [10]. PTA and PAK are associated with significantly higher incidence of acute rejection than SPK recipients [34]. Other risk factors include pancreas re-transplantation [10], absence of induction therapy or basiliximab and induction agent [8], donor age, number of HLA donor-recipient mismatch

In SPK recipients, monitoring of renal function and/or the performance of a renal biopsy had been advocated as an indirect method to establish the diagnosis and treatment of pancreas' acute rejection, since for many years it has been considered that acute rejection was present in the majority of the cases simultaneously in both grafts. However, it is now well documented

To diagnose pancreatic graft rejection, the only biochemical markers available are pancreatic enzymes (amylases and lipases), which are elevated in most of these episodes. Lipase increase is more specific than amylase [10]. On the other hand, in acute rejection, it is possible to observe changes in graft size and eco-structure, with an increase in the resistance index when performing a Doppler ultrasound. Both parameters allow to establish the diagnosis of suspected acute rejection, but they are not specific enough to establish confirmation. This sometimes leads to unnecessary or incomplete empirical treatments, with the consequent repercussion for the patient and the graft. In addition, pancreatic rejection, as recently observed, can also be medi-

Currently, pancreatic biopsy is considered the gold standard for etiologic diagnosis of graft dysfunction. In our center, pancreatic graft biopsy is performed per protocol at 3 weeks and 12months post-transplant, or indicated in the following circumstances (**Figure 1**): (1) patients in whom the existence of an acute rejection of the pancreatic graft is suspected due to biochemical parameters (increase in serum glycemia, amylases, and lipases), and/or ultrasound (increase in size, changes in the graft structure, and involvement of the graft), (2) in whom the existence of a chronic rejection is suspected due to a persistent increase in amylases or serum lipases, progressive increase in glycemia and glycosylated hemoglobin, and/or progressive decrease in C-peptide secretion, and (3) in whom the recurrence of diabetic disease is suspected due to detection or progressive increase of anti-GAD antibodies, and pathologic oral glucose tolerance test. To establish the severity of the histological lesion of acute rejection, the

that isolated rejection of one of the two organs occurs in up to 36% of cases [37].

pregnancy during the first 1–2 years of the transplant.

282 Organ Donation and Transplantation - Current Status and Future Challenges

[10], and the presence of donor-specific antibodies (DSA) [35, 36].

ated by antibodies, which requires a different and specific treatment.

Banff scheme should be taken as reference [38].

**9.1. Acute and chronic rejection**

transplant follow-up period.

Type 1 diabetes is the most frequent indication for pancreas transplantation. As described in the first section of this chapter, DM1 is an autoimmune disease, characterized by autoantibodies directed to β cells. Disease relapse in pancreas graft is a well-known risk for graft failure. It has been reported in up to 7% of all transplant recipients [39]. Induction and maintenance immunosuppression are likely the reason for such a low incidence. Some factors have been associated with an increased risk for disease relapse, such as donor-recipient sharing of HLA-DR alleles, particularly HLA-DR3 [39], and the increase in autoantibodies, particularly ZnT8A, predicts the risk of disease relapse [40]. As with primary disease, no treatment is established for the management of disease relapse. Increase in baseline immunosuppression maybe attempted. If a pancreas re-transplantation is indicated, recipients must be advised of the risk of relapse in the new graft.
