Nutrition and growth in inflammatory bowel disease

Abstract

Growth failure is common in children with inflammatory bowel disease (IBD), mainly those with Crohn's disease (CD). The prevalence of growth failure varies in different cohorts, mainly due to the heterogeneity of the population treated by the reporting centers (primary vs. referral), but can be as high as 40% of the cases. Factors related to growth impairment in CD include low dietary intake, stool loss, increased energy and nutrient requirements, the use of medications (for example, steroids interfere with the IGF-1 axis), disease activity (the effect of inflammation on growth), genetic background (parents height), and physical activity. In animals, malnutrition, genetic polymorphism, elevated pro inflammatory cytokines, and exposure to lipopolysaccharide are involved in growth impairment in IBD, while malnutrition, genetic polymorphism and increased inflammation have been shown to be associated with growth impairment in humans. Exclusive enteral nutrition (EEN) is the preferred first line treatment in CD. EEN induces remission, prolongs remission and affects growth failure via its effect on malnutrition and inflammation. However, similar to drug treatment, EEN effect on growth failure is limited, most probably due to incomplete control of inflammation. Children with IBD should be assessed for growth on diagnosis and on each follow-up visit. New nutritional strategies, identification of genetic polymorphisms that respond to EN, and methods to increase lean body mass (physical activity) are needed in order to improve growth in our IBD patients.