Although our general understanding of food hypersensitivity has improved in recent years, gastrointestinal food protein-induced diseases still pose diagnostic and therapeutic dilemmas.
Food allergy in children and adults may involve any part of the gastrointestinal tract. Clinical presentations include protein-induced enterocolitis syndrome, enteropathy and proctocolitis, as well as eosinophilic gastroenteritis and related disorders. For many of these conditions, our understanding of the pathophysiology is incomplete. Manifestations are mostly non-IgE mediated, and skin prick testing and measurement of food-specific IgE antibody levels are of limited diagnostic value. Atopy patch testing may be of benefit in identifying food items associated with late-onset gastrointestinal reactions. A definitive diagnosis of gastrointestinal food allergy, however, still relies on formal food challenges. Depending on the clinical presentation, gastrointestinal biopsies may be required. In infancy, hypoallergenic formula or maternal elimination diets have been shown to effectively control the gastrointestinal manifestations of food allergies. Growth parameters and micronutrient levels need to be carefully monitored while on elimination diets for prolonged periods. In older children and adults with eosinophilic gastrointestinal disorders, the response to dietary restriction is variable. Corticosteroids may be required to control symptoms in those who failed to respond to hypoallergenic diets. In eosinophilic esophagitis, steroids can be administered topically in the form of swallowed aerosols. Leukotriene receptor antagonists and other novel therapies may be useful as steroid-sparing agents.
Early diagnosis and treatment of food protein-induced gastrointestinal diseases may prevent significant nutritional complications. Further research is needed to develop diagnostic tools for these mainly cell-mediated disorders.
Departments of Allergy and Gastroenterology & Clinical Nutrition, Royal Children's Hospital, and Department of Paediatrics, University of Melbourne, Melbourne, Australia
Correspondence to Dr Ralf Heine MD FRACP, Paediatric Gastroenterologist, Department of Allergy, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052, Australia Tel: +61 3 9345 5701; fax: +61 3 9345 4848; e-mail: firstname.lastname@example.org