Food Protein Induced Enterocolitis syndrome – FPIES
Dr Marie Wheeler, Consultant Paediatrician, MB ChB MRCP DCH, at Gloucestershire Royal Hospital, explains.
Many acute allergic reactions to food (Type 1 or IgE reactions) are fairly easy to spot with symptoms such as an urticarial rash (hives), eye or facial swelling (periorbital or facial oedema) occurring very soon after the food was eaten.
There are also a group of foods that are the most common offenders including cows milk protein, egg, nuts, fish and seafood; less common offenders include soya, peas and seeds, and celery. Food Protein Induced Enterocolitis Syndrome (FPIES) however is rather different, making its diagnosis more difficult.
Causes – Milks and solid foods
FPIES may also be caused by solid foods which can almost be more worrying. The symptoms will then appear as solids are introduced into the infant diet, usually in the UK from 4-6 months of age.
A baby may present in the first 6 months of life, with severe vomiting and sometimes with diarrhoea. In severe acute cases this may lead to dehydration and lethargy/floppiness and the child may finally be taken to an emergency department because he/she is showing signs of having a severe infection. It is not uncommon for a baby to be admitted once or even twice with a likely diagnosis of a severe infection before the diagnosis of FPIES is considered, partly because the symptoms are not particularly indicative of an ‘allergy’. Chronic FPIES can cause poor weight gain so occasionally presents in this way.
The diagnosis is also not straightforward because there is no blood test for FPIES as there is for allergy. If the child remains well once the implicated food is removed from the diet, the diagnosis of FPIES can usually be established on clinical grounds. At times, it can be difficult to know if the suspected food really is the culprit, so in these rare cases a food challenge in the hospital setting may be required. This kind of challenge may be performed, under observation within the hospital setting, sometimes with an intravenous line in place, in case of rapid vomiting during the challenge.
The differential diagnosis of FPIES is wide and includes other allergic food disorders, infectious disease, severe gastroesophageal reflux disease, less commonly anatomical intestinal obstruction as well as others including metabolic diseases.
Management and Treatment
If there were an acute reaction, the management relies on rehydration (sometimes requiring intravenous fluids) and not on the use of antihistamines or intramuscular adrenaline, as in acute food allergy reactions.
Extensively hydrolysed formula milks (Nutramigen Lipil or Pepti) or essential amino acid milks (Neocate LCP or Nutramigen AA) are recommended rather than soy-based formula, in part, because many babies with cow’s milk FPIES will also have soya FPIES. In 10%-15% of infants, an amino acid formula (e.g. Neocate LCP or Nutramigen AA) is needed. In severe cases, temporary bowel rest as well as IV fluids may be necessary.Weaning onto Solids
Introducing vegetables and fruits only and leaving out cereals at 6 months of age may be one initial solution to try. If tolerated, grains, legumes, and poultry can be introduced to the diet. However, because, often, several foods cause symptoms in solid-food FPIES, it may be best to avoid these foods in the first year of life. Tolerance to one food from each high-risk group – for example soy in the legume group, chicken in the poultry food group, or oat from the grains group – gives a good indication that other foods from the same group should be tolerated, making weaning easier, which can be useful to know.
First published September 2013