Energy expenditure and body composition in children with Crohn's disease: effect of enteral nutrition and treatment with prednisolone

Background-Malnutrition and growth retardation are common complications of Crohn's disease in children. The contribution of resting energy expenditure (REE) to malnutrition is unclear. Aims-To characterise the REE and body composition in children with Crohn's disease and compare them with normal controls and patients with anorexia nervosa; to compare the effects of prednisolone and enteral nutrition on energy expenditure and body composition. Subjects-Twenty four children with Crohn's disease, 19 malnourished females with anorexia nervosa, and 22 healthy control subjects were studied. Methods-In children with Crohn's disease measurements were done when the disease was acute and repeated at one and three months after treatment with either prednisolone or enteral nutrition. Resting energy expenditure was measured by indirect calorimetry and body composition by anthropometry, bioelectrical impedance analysis, total body potassium, (H2O)-O-18, and bromide space studies. Results-Body weight and ideal body weight were significantly lower in patients with Crohn's disease than in healthy controls. Lean tissue was depleted and there was an increase in extracellular water. Per unit of lean body mass, there was no difference between REE in patients with Crohn's disease and controls, whereas patients with anorexia nervosa had significantly reduced REE. With enteral nutrition all body compartments and REE increased significantly (p<0.001). In a subgroup of age-matched men there was a significant increase in height after three months of enteral nutrition compared with prednisolone (p<0.01). Those treated with steroids did not show a significant change in height but did show an increase in all body compartments. However, intracellular water as well as lean body mass accretion were significantly higher in the enteral nutrition group than in the prednisolone group. Conclusions-Despite being malnourished, children with Crohn's disease fail to adapt their REE per unit of lean body mass. This might be a factor contributing to their malnutrition. Lean tissue accretion is higher in patients treated with enteral nutrition than in those treated with prednisolone.