The role of endoscopy in the small intestinal transplant recipient: a review.

Intestinal transplantation (ITx) is the treatment of choice for patients with intestinal failure who have developed life-threatening complications related to long-term parenteral nutrition. Patients may also undergo ITx as part of a combined liver-intestine or multi-visceral transplant for a variety of indications, most commonly intestinal failure-associated liver disease or porto-mesenteric thrombosis. Endoscopy plays a critical role in the post-transplant management of these patients, most commonly in the diagnosis and management of rejection, which occurs in up to 30-40% of patients within the first year post-transplant. With a lack of noninvasive biomarkers to identify the presence of rejection, endoscopy and biopsy remain the gold-standard for its diagnosis. Endoscopic evaluation of the graft is also important in the identification of other complications post-ITx, including post-transplant lymphoproliferative disorder, graft-versus-host disease, and enteric infections. Each patient's post-transplant anatomy may be slightly different, making endoscopy sometimes technically challenging and necessitating clear and frequent communication with the surgical team in order to help identify the highest-yield approach. Herein, we review the most common pathologies found endoscopically in the post-ITx patient and describe some of the unique challenges the endoscopist faces when evaluating these complex patients.