Long term evolution of small bowel grafts and the risk of chronic rejection are becoming increasingly important in the patients’ follow up. As part of our systematic protocol, we perform endoscopies every 5 years, in order to look for preclinical signs of rejection. We report here the results of the 10-year protocol biopsies and discuss our findings.

Patients & Methods: Seventeen children who underwent an intestinal transplantation (ITx) in our unit were followed for a median of 10.5 years (8 to 12 years). Nine received a combined liver-small bowel Tx (one re-transplantation), 8 an isolated small bowel Tx, 5/17 together with the right colon. None had symptoms at the time of endoscopy, and none had been treated for rejection in the previous year. Small bowel graft biopsies and colon graft biopsies in 5/17 were reviewed by the same expert pathologist.

Results: Small bowel biopsies showed normal villi in all patients and in 2 cases only an increase in intra-epithelial lymphocytes. Mononuclear cells were often increased in the lamina propria (12/17). This infiltrate was moderate in most cases (8/12), mild in 3 others, and important in 1 case. Eosinophils were increased in 8/17 patients but numerous in only 1 case. The intestinal glands were often normal except in 4 cases, in which apoptotic cells were increased, still less than 6 per 10 glands. A mild fibrosis of the deep lamina propria was observed in only 1 case, in a boy who later developed inflammatory bowel disease-like stenosis of the ileocecal valve. For the 5 patients with colon graft biopsies, mononuclear cells were increased in the lamina propria in most cases (4/5: 1 mild, 2 moderate et 1 prominent), associated with an increase in eosinophils in all patients, important in one case. Colonic glands were usually normal except in 1 case, who had acute infectious diarrhea a few weeks before, where a focal increase of apoptosis (10/10 glands) was seen. No fibrosis was observed in the lamina propria of colon graft biopsies.

Discussion & Conclusion: Most of the long tem control biopsies of these asymptomatic patients showed chronic inflammatory lesions, usually mild and not specific often associated with an increase of eosinophils. There was no sign of rejection, and the only case with increased apoptosis was probably post-infectious. Fibrosis, that could have been an early sign of chronic rejection, was seen in one patient only, who later developed stenosis of the valve, a probable immune-mediated complication. No occult infection was diagnosed. These results are reassuring for the long term evolution after intestinal transplantation, when the patients are asymptomatic.