Surveillance and monitoring of pancreas allografts

Recipients of pancreas allografts are routinely monitored by clinical and biochemical markers that include ultrasound and imaging of the pancreas, serum levels of amylase, lipase, blood glucose, C-peptide, and immunosuppressive drug levels and measurement of urinary amylase for bladder-drained grafts. The specificity of many of these tests is rather low, with a predictive value for acute rejection generally around 50 to 75%. Biopsies of pancreatic allografts remain the most specific marker for acute rejection of the pancreas and help explain other reasons for pancreatic dysfunction. Protocols of surveillance biopsy of solitary pancreas allografts may be associated with a beneficial increase in the one-year graft survival rate and can minimize graft loss secondary to acute rejection. Fine Needle Aspiration Cytology is a low risk procedure for monitoring the intra-graft events and constitutes a complimentary technique to histology. The purpose of this review is to describe the overall clinical monitoring of pancreas transplant recipients with special emphasis on the role of pancreatic histology and to describe the clinicopathologic correlation of the various morphologic findings.