Immunopathology of the digestive apparatus in infancy

: The infant acquires immunological competence in the neonatal period through the passage of antigens from the enteric lumen through gut-associated lymphoid tissues, principally the Peyer's patches and the appendix. Immune deficient mechanisms may be involved in several gastrointestinal diseases manifesting in the neonatal period as well as throughout childhood. Principally among these are neonatal necrotising enterocolitis, atopy and food intolerances, coeliac disease, cow's milk protein intolerance, diarrhoea associated with hypogammaglobulinaemia, malnutrition and inflammatory bowel disease. The mechanism whereby immune reactions are involved in the pathogenesis of these diseases is discussed.