ObjectiveThe purpose of this study was to initially determine if growth hormone or nutrients, given alone or together, could enhance absorption from the remnant small bowel after massive intestinal resection. If clinical improvement were observed, this therapy would then be used to treat patients with the short-bowel syndrome over the long term. Summary Background DataPatients who undergo extensive resection of the gastrointestinal tract frequently develop malabsorption and require long-term parenteral nutrition. The authors hypothesized that the administration of growth factors and/or nutrients could enhance further compensation of the remnant intestine and thereby improve absorption. Specifically, animal studies have shown that there is enhanced cellularity with the administration of growth hormone (GH) or glutamine (GLN), or a fiber-containing diet. MethodsInitially, 17 studies were performed in 15 total parenteral nutrition (TPN)-dependent short-bowel patients over 3 to 4 weeks in the clinical research center; the first week served as a control period, and during the next 1 to 3 weeks, the specific treatment was administered and evaluated. Throughout the study, food of known composition was provided and all stool was collected and analyzed to determine absorption across the remaining bowel. The effect of a high-carbohydrate, low-fat diet (DIET), the amino acid glutamine (GLN) and growth hormone (GH) administered alone or in combination with the other therapies (GH + GLN + DIET) was evaluated. The treatment was expanded to 47 adults (25 men, 22 women) with the short-bowel syndrome, dependent on TPN for 6 ± 1 years. The average age was 46 ± 2 years, and the average jejunal-ileal length was 50 + 7 cm (median 35 cm) in those with all or a portion of colon and 102 ± 24 cm (median 102 cm) in those with no colon. After 28 days of therapy, the patients were discharged on only GLN + DIET. ResultsThe initial balance studies indicated improvement in absorption of protein by 39% accompanied by a 33% decrease in stool output with the GH + GLN + DIET. In the long-term study, 40% of the group remain off TPN and an additional 40% have reduced their TPN requirements, with follow-up averaging a year and the longest being over 5 years. 243

The combined administration of growth hormone, glutamine, and a modified diet enhanced nutrient absorption from the remnant bowel after massive intestinal resection. These changes occurred in a group of patients that had previously failed to adapt to the provision of enteral nutrients. This therapy may offer an alternative to long-term dependence on total parenteral nutrition for patients with severe short bowel syndrome.

Treatment with GH + diet or GH + Gln + diet initially permitted significantly more weaning from PN than Gln + diet. Only subjects receiving GH + Gln + diet maintained this effect for at least 3 months.

Approximately half of a group of patients, thought to have absorptive surface area inadequate to be independent of TPN support, can maintain themselves on enteral feedings after this intestinal rehabilitation program. Because of the risk, costs, and alterations in lifestyle associated with long-term TPN or intestinal transplantation or both, it seems prudent to consider a program of bowel rehabilitation with an individual patient before embarking on another therapeutic plan.