ENERGY EXPENDITURE, CYTOKINES AND THERMOGENIC HORMONES IN CHILDREN WITH CROHN'S DISEASE

Abstract

Crohn's disease (CD) in children is often complicated by malnutrition. Energy imbalance is a contributing factor and cytokines could play a role in this imbalance. The aim of the study was to investigate the resting energy expenditure (REE) in children with CD and examine its relationship to cytokines and thermogenic hormones. 11 children (7 male), mean (SD, range) age of 12.4 (±2.3, 8.3-14.9) yr with moderately severe CD were studied. REE (indirect calorimetery), body composition, 24 hr urinary catecholamines (epinephrine, norepinephrine, dopamine), plasma (ELISA) tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were measured when the disease was active {Paediatric Crohn's Disease Activity Index (PCDAI≥30)} and repeated 5-8 weeks later when in remission (PCDAI <15) after treatment with prednisone or enteral nutrition. REE and body composition was measured in 12 healthy children as controls. Table A = Active disease, before treatment. B = In remission, after treatment. IBW=Ideal body weight, LBM=Lean body mass. *p <0.05 compared to controls. Data expressed as mean ±SD. Despite being underweight the total%predicted REE of CD was not different from controls. Per LBM, patients with active CD had higher REE compared to controls. There was a significant decrease in TNF-α (from 2.74±1.73 to 1.93±0.66 pg/ml), IL-1β (1.81±1.53 to 1.14±1.03 pg/ml) and IL-6 (13.49±10.89 to 10.29 ±9.13 pg/ml) levels after treatment (paired t-test). Catecholamines showed a trend to reduction. We conclude that cytokines play a role in the anorexia and malnutrition seen in active CD and these patients fail to down-regulate their energy expenditure in response to weight loss. This lack of adaptation in REE could be a contributing factor to their malnutrition.