Introduction : Very late survivors (VLS) after small bowel transplantation (SBT) have frequent early and late complications, often involving intestinal graft. We aimed to describe intestinal histology and function in this group of patients.

Material and methods : All survivors 10 years after SBT were selected (n=26 (62% including colon), 19 Liver-SBT and 7 isolated SBT). Stools output were collected during 3-day metabolic periods to assess intestinal absorption: nitrogen, fat, and total energy were determined by nitrogen analysis. Quantification of carbohydrate-derived energy absorbed was calculated by subtracting the energy associated with the nitrogen and fat components from the total energy. Blood citrulline, fecal-alpha1-antitrypsin clearance (a-1ATc), elastase and calprotectin were measured to evaluate functional enterocytic mass, protein-losing enteropathy, epithelial inflammation and exocrine pancreatic function. Histology with C4d immunostainingof the last ileal biopsy performed was assessed.

Results :Mean age of the 26 patients at SBT was 4,6 year-old. Sixpatients experienced graft loss and 4 of them died at a mean age of 22 year-old (15-25). Energetic absorption and histology were evaluated in 23 and 12 patients respectively. 17/23 (74%) patients had a preserved intestinal graft, including 3 retransplanted patients. Oral caloric intake and total caloric absorption were 2200 (500-4300) kcal/d and 88% respectively (lipids 84%, glucids 94%, protides 83%). Citrulline, a-1ATc, fecal calprotectin and fecal elastase were normal. Histological lesions observed in the 12 VLS with functioning graft were an increase of lymphocytes and eosinophils in the lamina propria, an increase of intra-epithelial lymphocytes, a mucosal fibrosis and a gland distortion in  92%, 33% , 25% patients and 17% of the patients respectively. No vascular lesion was observed and  C4d was negative in all.

Conclusion :Despite numerous digestive complications, VLS have subnormal histology and excellent intestinal functions with normal growth/oral intake.