Pancreas irradiation for treatment-resistant acute cellular rejection in a severely immunocompromised pancreas-after-kidney transplant recipient-case report.

Treating acute rejection of a pancreas transplant in a severely immunocompromised patient with viral opportunistic infection is challenging due to the balance of rescuing from rejection without worsening the morbidity of infection and prolonging the infection episode. We present a case involving a pancreas-after-kidney transplant in a patient with cytomegalovirus (CMV) high-risk discordance (donor positive/recipient negative) and chronic lymphopenia who developed difficult-to-treat CMV disease approximately 6 months after pancreas transplantation. Following the withdrawal of the antimetabolite due to the persistent CMV DNAemia and lymphopenia, the patient experienced acute pancreas rejection without adequate and sustained response to treatment with steroids and thymoglobulin. Moreover, systemic treatment for rejection resulted in higher CMV replication. Pancreas transplant irradiation was performed 5 months after initial pancreatic enzymes increase, resulting in a decrease of lipase below the normal range for 4 to 6 months thereafter. While pancreatic β cells function appeared to be preserved based on stimulated C-peptide testing, the patient experienced ongoing CMV DNAemia despite the treatment and eventually presented with hyperglycemia and diabetic ketoacidosis requiring insulin initiation. Pancreas allograft irradiation may be an option for the treatment of acute pancreas rejection. Appropriate timing to implement this modality and long-term endocrine outcomes need to be prospectively studied.