The effect of disease, drug, and diet on whole body protein metabolism in adolescents with Crohn disease and growth failure

Chronic intermittent elemental diet improves growth failure in children with Crohn's disease

Growth failure often complicates Crohn's disease in pediatric patients and is principally due to inadequate caloric intake. To assess whether intermittent courses of an elemental diet could reestablish growth, 8 children (aged 9.8-14.2 yr) with Crohn's disease and growth failure entered into a prospective trial. Each patient was studied during an observation year on standard therapy, then for an experimental year during which they received enteral elemental diet 1 out of 4 mo. An age- and disease-matched control group of 4 patients was treated by conventional medical therapy during both years. Elemental diet therapy was administered nocturnally, at home, by continuous nasogastric infusion and increased the daily caloric intake by 25% (p less than 0.01). Anthropometric measurements demonstrated significant height and weight gains in the elemental diet group vs. controls (p less than 0.01). Crohn's disease activity index and prednisone intake decreased significantly in patients receiving elemental diet therapy when compared with themselves and with controls on conventional medical therapy (p less than 0.05). In contrast, the rate of pubertal development was similar in both groups irrespective of the treatment modality. This study demonstrates that chronic intermittent elemental diet effectively reverses growth arrest, while decreasing prednisone requirements and Crohn's disease activity index in pediatric Crohn's disease patients prior to puberty.

Inflammatory bowel disease in children

Ulcerative colitis and Crohn's disease are chronic intestinal disorders with diverse presentations that must be familiar to pediatricians. The subtlety of clinical signs and symptoms may be overshadowed by extraintestinal complications. An awareness of diagnostic techniques and the necessity of an integrated approach of medical and surgical management is emphasized. Potential complications may affect prognosis and require their own specific therapy. The management of these disorders entails an individualized assessment of the extent and severity of intestinal involvement, extraintestinal complications, as well as ongoing medical, nutritional, and emotional support.

Nutritional therapy of Crohn's disease in childhood

Crohn's disease is a chronic, incurable inflammatory bowel disease commonly diagnosed in childhood and adolescence. Growth failure represents a common, serious complication unique to the pediatric age group. Although the etiology of growth failure is multifactorial, malnutrition due to inadequate nutrient intake is the primary cause. Recent studies have demonstrated that nutritional supplementation through an enteral or parenteral route restores body composition and reverses linear and ponderal growth failure. The development of elemental diets that can be administered nasogastrically at home has afforded a more practical, less expensive, and less hazardous method of providing Crohn's disease patients with nutritional supplementation and bowel rest. Elemental-diet therapy has also been shown to be a safe, effective method of inducing a remission in acute Crohn's disease. Further studies are required to develop optimal nutritional therapy which may sustain long-term remission in this disease.

Protein metabolism in inflammatory bowel disease

Major loss of body protein mass in inflammatory bowel disease is much less common than weight loss, which is often attributable to losses of other body, particularly water and fat. It does occur, however, in a few patients, especially in those with compromised food intake. It is due principally to the combined effects of diminished intake and excessive intestinal losses of amino nitrogen. Nitrogen metabolism is influenced not only by protein nutritional state and net nitrogen intake but also by disease activity. There is some evidence for abnormally low secretion of growth hormone in adolescents with inflammatory bowel disease and growth failure. Low serum albumin concentrations are not necessarily related to protein undernutrition and are the combined result of relatively reduced albumin synthesis, increased intestinal losses, and maldistribution between intravascular and extravascular spaces. Concentrations in the plasma of IgG and acute phase reactants may be raised despite increased losses into the bowel lumen. The prevention of total body protein depletion is achieved principally by maintaining adequate and often not supranormal intakes of a balanced source of amino nitrogen in a balanced diet given orally, enterally, or parenterally, combined with a medical or surgical approach to reduce disease activity: supranormal energy intakes are not beneficial.

Somatomedin-C levels in growth-impaired children and adolescents with chronic inflammatory bowel disease

The relationship between caloric insufficiency and impaired growth in children with chronic inflammatory bowel disease has been increasingly recognized in recent years. The mechanism by which nutritional insufficiency leads to decreased growth in these children is unclear. Our study suggests that chronic undernutrition lowers circulating somatomedin-C, which is known to exert anabolic effects on peripheral tissues. Therapeutic intervention that increases caloric intake results in improved somatomedin-C levels and growth velocity. Monitoring somatomedin-C levels in growth-impaired children with inflammatory bowel disease provides an important marker of nutritional sufficiency and reversibility of growth retardation.

Mineral balance during nutritional supplementation in adolescents with Crohn disease and growth failure

The adaptive response of whole body mineral metabolism and collagen turnover to nutritional supplementation was determined in adolescent males with Crohn disease and growth failure. Body calcium, magnesium, phosphorus, and nitrogen status was characterized in six patients before and after 3 weeks of nutritional supplementation and in five healthy age- and sex-matched controls by the metabolic balance technique; collagen turnover was assessed by urinary hydroxyproline excretion. Fecal calcium (P less than 0.05), magnesium (P less than 0.01), and nitrogen (P less than 0.01) losses were significantly greater in the Crohn disease patients compared with the controls; after dietary supplementation, only fecal magnesium excretion increased further (P less than 0.001). Approximately twofold increases in phosphorus (P less than 0.001), nitrogen (P less than 0.02), and calcium (P less than 0.05) retention occurred with nutritional supplementation, whereas the marked renal conservation of phosphorus (P less than 0.001) suggested that this mineral was a limiting nutrient. Urinary hydroxyproline excretion was reduced (P less than 0.05) compared with the control values; however, with nutritional supplementation, urinary hydroxyproline excretion increased significantly (P less than 0.02), suggesting that the soluble fraction of tissue collagen was rapidly turning over during nutritional rehabilitation. These findings suggest that the mineral deficiencies present in adolescents with Crohn disease and growth failure can be reversed with nutritional supplementation. Furthermore, the improvement in nutritional status is reflected in the restoration of collagen-containing tissues of the body. However, nutrient imbalances may be present during nutritional therapy, thereby preventing optimal recovery from malnutrition.

Nutritional management of inflammatory bowel disease

Malnutrition and growth failure are frequent complications of inflammatory bowel disease in childhood owing to inadequate dietary nutrient intakes, excessive intestinal losses, malabsorption, and increased nutrient requirements. Aggressive nutritional therapy is indicated for primary and supportive management of disease activity, drug nutrient interactives, individual nutrient abnormalities, and the overall complications of inflammatory bowel disease, malnutrition, and growth failure. The prevention of nutritional disorders in inflammatory bowel disease is accomplished by monitoring anthropometric and biochemical indices and by instituting appropriate enteral or parenteral nutritional therapy when indicated.