Non-IgE-mediated food allergy is often referred to as gastrointestinal (gut) food allergy. For this reason, it is sometimes confused with food intolerance. Reactions happen because of an abnormal immune response to food proteins and are generally delayed (1 to 72 hours after eating or drinking the food).
A non-IgE-mediated food allergy cannot be diagnosed with a skin prick test or IgE antibody blood test. A diagnosis can only be made after an elimination diet.
There are a few different types of non-IgE-mediated food allergy:
Food Protein-Induced Allergic Proctocolitis (FPIAP)
FPIAP occurs because of inflammation in the large intestine caused by allergy. FPIAP usually occurs in babies who are breastfed but can also occur when cow’s milk (dairy) or soy-based formula are started.
Signs of FPIAP can include blood and mucus in stools and diarrhoea. Signs usually start in early infancy. Babies with FPIAP are otherwise healthy and growing well.
Food Protein Enterocolitis
(FPE)
FPE occurs because of inflammation in the small intestine caused by allergy. FPE occurs in babies soon after food is introduced.
Signs of FPE can include diarrhoea, abdominal pain, vomiting and poor weight gain and growth. Babies are often unsettled and irritable and sleep poorly. Growth and development can also be affected.
Food Protein-Induced Enterocolitis Syndrome (FPIES)
FPIES, pronounced F-pies, is a type of non-IgE-mediated food allergy. FPIES is a delayed gut allergic reaction that usually occurs in the first two years of life, most often during early infancy (4-6 months of age) when a baby starts eating solids. FPIES reactions can occur in the first few months of life in non-breastfed babies. FPIES rarely occurs in fully breastfed babies.
Eosinophilic Oesophagitis (EoE)
EoE is an allergic disease affecting the oesophagus, the muscular tube that takes food and drink from the mouth to the stomach. In EoE, the oesophagus becomes inflamed, resulting in pain, swelling and redness. This inflammation can be caused because of an allergy to food(s) and/or allergens in the environment, such as tree and grass pollen. EoE is more common in people with other allergies such as allergic rhinitis (hay fever) and asthma.