New treatment for patients with short-bowel syndrome: growth hormone, glutamine and a modified diet.

Abstract

After massive enterectomy, the remnant bowel must undergo both morphologic and physiologic adaptation if the patient is to wean to volitional enteral support. Those patients who are unable to adapt require long‐term total parenteral nutrition (TPN) with its concomitant high cost and metabolic anomalies. Previously, it was believed that adaptation ceased after a period of 1 to 2 years. In 1992, Byrne et al presented the theory that further adaptation could be elicited in a group of 8 patients who had been on TPN for up to 6 years by treatment with a combination of growth hormone, free glutamine, and a diet high in fiber and low in fat.1 This paper did not delineate the specific mechanisms or present long‐term results. The current study involves 47 patients with short‐bowel syndrome dependent on TPN for an average of 6 years. Average age was 46 with a mean jejunoileal length of 50 ± 7 cm. Half of the patients had <35 cm of small bowel. Etiologies included volvulus, SMA thromboses, or adhesions in the vast majority. Eleven patients had Crohn's disease. All but four patients had at least some colon or rectum remaining in the circuit.Patients were admitted to an inpatient residential environment (the Nutritional Restart Center), where baseline studies of nutrient balance were obtained on the patient's normal intake. They were then placed on a diet high in complex carbohydrates and low in fat for the next 3 weeks. Feedings were divided into six equal parts and isotonic fluids were allowed ad libitum. Groups were also randomized to receive human growth hormone, 0.14 mg/kg/d, or enteral glutamine, 0.6 mg/ kg/d, or both. At the conclusion of the 4‐week stay, patients were discharged on only the diet and supplemental glutamine.The combination of growth hormone, glutamine, and the diet led to a near 40% improvement in daily nitrogen balance and a 33% decrease in stool weight. Sodium balance was similarly improved, although this may reflect growth hormone's effect on water retention. Twenty‐seven patients were able to eventually be weaned off TPN. There was no significant difference in small bowel length or the presence or absence of colon compared with those patients who still required TPN. Eight patients eventually required reinstitution of TPN over the long term, usually due to recurrence of previously quiescent inflammatory bowel disease or dietary noncompliance. Nonetheless, 60% of patients remained either completely free of TPN or required TPN at a lower rate.Nutritional indices were not changed. Serum albumin remained in the 3.6 to 3.8 range in all groups, both at baseline and after the period of intervention. Weight remained stable, except for the eight patients requiring continued TPN who showed an average of a 2‐kg weight loss. Cost savings even in those patients who could not be completely weaned from TPN averaged $80,000 per year. This is exclusive of the cost of the diet or supplemental growth hormone and glutamine.