Measurement of Basal Metabolism in Patients With Crohn's Disease and Ulcerative Colitis and Correlation With Disease Activity.

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are associated with an increased risk of malnutrition and growth impairment in pediatric patients. Chronic inflammation, reduced oral intake, malabsorption, and increased metabolic demand may contribute to altered nutritional status and increased resting energy expenditure (REE).

Resting energy expenditure represents the amount of energy required to maintain basic physiological functions at rest and accounts for most daily energy consumption. Accurate evaluation of REE is important to optimize nutritional support and avoid underfeeding or overfeeding in children with IBD.

This study is a national multicenter prospective observational no-profit study involving pediatric patients aged 6 to 17 years with a new diagnosis of IBD according to ECCO/ESPGHAN criteria. Approximately 50 patients are expected to be enrolled.

REE will be measured using indirect calorimetry and compared with predictive equations. Clinical and laboratory parameters routinely collected during standard clinical care will also be evaluated, including disease activity indices (PUCAI/PCDAI), anthropometric measurements, biochemical parameters, fecal calprotectin, dietary intake, physical activity questionnaires, and endoscopic scores.

Data will be collected at diagnosis, after induction therapy, and during follow-up visits. The study aims to identify possible correlations between REE, disease activity, and dietary or pharmacological treatments in pediatric patients with IBD.