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A Case Report On Food Protein Induced Enterocolitis Syndrome (FPIES) In An Infant
By - Dr. Bhaswati Acharyya
DCH, MD (Paed), DNB (Paed), DNB (Gastro), MRCPCH (UK), MRCP (Edin) Fellowship in Paediatric Hepatology & Liver Transplantation (UK) Fellowship in Paediatric Gastroenterology (UK) Consultant Paediatric Gastroenterologist & Hepatologist, AMRI Hospitals, Kolkata
Initial Case Presentation:

A 3-month-old unwell baby girl presented with vomiting, lethargy, and oliguria to a Paediatric Gastroenterologist and was admitted in the hospital.


The baby was born full term and healthy at birth, weighing 3.8 kgs (weight/age z score = 0 to -2) to non-consanguineous parents. 21 days after birth, she developed persistent vomiting and diarrhea for which she was treated with antibiotics. This reduced her stool frequency, but the symptoms persisted. Her weight gain was very poor. At 6 weeks, she weighed about 3.7 kgs and continued to pass stool at an increased frequency.

Apart from breastfeeding, the baby was top fed and made to change 2 different cow’s milk formulas and then was kept on soy formula. At 3 months of age, she was very unwell and had to be brought to the hospital.


On primary examination at the time of admission, the baby appeared to be lethargic and oliguric due to persistent vomiting, severe dehydration, tachycardia and tachypneia. She weighed 3.4 kgs (weight/age z score = < -3 = severely underweight). We admitted her in the Neonatal Intensive Care Unit and she was resuscitated, rehydrated and stabilized.

Laboratory examination upon admission showed:

  • Total Leucocytes Count: 19000/mcL
  • Hemoglobin: 8.1 g/dL
  • Platelets: 400000/mcL
  • CRP: 52 mg/L
  • Urea: 38 mg/dL
  • Cr: 0.7 mcg/mL
  • Na: 124 mEq/L
  • K3 albumin: 1.8 g/dL

Venous Blood gasses

  1. pH: 7.28
  2. Lactate: 4.5 mmol/L
  3. Bicarbonate: 5 mmol/L
  4. Base excess: –20 mEq

Endoscopy revealed a complete non-development of the villous (Refer Figure 1). We excluded metabolic disorders and structural intestinal problems.


Chronic vomiting, diarrhea, dehydration, lethargy and weight loss are indicative of Food Protein-Induced Enterocolitis Syndrome (FPIES). Based on the clinical presentation, she was a suspect of FPIES. At first, intravenous fluid resuscitation was done. We eliminated cow’s milk and soy protein from her diet and on day 2 started with amino acid-based infant formula  which was well tolerated by her. A reduction in diarrhea was observed from the 4th day and by the 8th day the patient was stable enough to be discharged from the hospital.

figure 1Endoscopy revealed a complete non-development of the villous.

Weight-for-age GIRLS

Birth to 6 months (z-scores)

figure 2WHO Child Growth Standards chart sourced from Accessed on 16.08.2018

Her weight at the time of discharge was 3.9 kgs. The patient remained symptom-free in the following days and reported back to the outpatient department 7 days later. With treatment on AAF (Amino acid formula), she showed substantial weight gain and was now at 4.6 kgs (weight/age z score = -2 to -3) climbing on the growth curve (Refer Figure 2).


Food protein-induced enterocolitis syndrome (FPIES) is considered the most severe of the non-IgE-mediated gastrointestinal (GI) food allergies that typically presents in infancy. Onset can occur within 1–4 hours after the ingestion of the offending foods and children typically are negative to food specific IgEs.1

It has been hypothesized that ingestion of food allergens causes local inflammation leading to increased intestinal permeability and fluid shift, which results in the symptoms of vomiting, diarrhea and lethargy which are all characteristic of FPIES.2 Severe cases can progress to hypothermia, methemoglobinemia, acidemia, and hypotension, mimicking sepsis.1

FPIES does not occur in breastfed infants and seems to require direct ingestion of the allergen by infant.3 Cow’s milk, soy and grains are commonly reported triggers of FPIES.1 In the present case, the baby was allergic to cow’s milk and soy protein and its elimination led to symptom improvement.

Symptoms of FPIES overlap with other medical conditions, so diagnosis can be challenging.

The diagnosis is based on medical history and absence of symptoms when the causative food is eliminated from the diet. FPIES food challenge generally is not performed before 2 yrs of age.3

Management of FPIES includes elimination of food allergen, guidance on foods that can be consumed and continuous assessment of nutritional intake as well as growth and development. The present case was a chronic FPIES with symptoms including vomiting, chronic diarrhea and failure to thrive. Typically infants with chronic FPIES usually return to their usual state of health within 3-10 days of switching to a hypoallergenic formula.1 European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines recommend the use of AAF for the treatment of FPIES, particularly in association with growth faltering.4

After treatment with AAF, we observed considerable improvement in her weight. The decision to choose an AAF over an eHF was because eHF contains residual peptides and may not give complete symptom resolution. The choice of formula can be made on the basis of the clinical presentation but studies have shown that eHF may not be suitable for treatment of FPIES in all infants.5,6


Delay and misdiagnosis of FPIES is common and this entity needs to be understood well. The present case illustrates the importance of appropriate nutritional management with an AAF in FPIES to ensure normal growth and development.


  1. Nowak-Wegrzyn A. et al. International consensus guidelines for the diagnosis and management of food protein–induced enterocolitis syndrome: Executive summary—Workgroup Report of the Adverse Reactions to Foods Committee, American Academy of Allergy, Asthma & Immunology. J allergy clin immunol april 2017.

  2. Caubet J, Nowak-Wegrzyn A. Current understanding of the immune mechanisms of food protein-induced enterocolitis syndrome. Expert Rev Clin Immunol 2011;7:317–327.

  3. Koletzko B et al. Pedaitric Nutrition in Practice. 2nd revised edition, Karger. World review of Nutrition and dietetics, Vol 113.

  4. Koletzko S, Niggemann B, Arato A, et al. Diagnostic approach and management of cow’s-milk protein allergy in infants and children: Espghan GI committee practical guidelines. J Pediatr Gastroenterol Nutr. 2012;55(2):221-229.

  5. Vanderhoof JA et al. Intolerance to protein hydrolysate infant formulas: an underrecognized cause of gastrointestinal symptoms in infants. J Pediatrics 1997;131:741–774.

  6. Kelso JM, Sampson HA. Food protein-induced enterocolitis to casein hydrolysate formulas. J Allergy Clin Immunol 1993; 92:909–910.

Important Notice:

The World Health Organization (WHO)* has recommended that pregnant women and new mothers be informed of the benefits and superiority of breast-feeding, in particular, the fact that it provides the best nutrition and protection from illness for babies. Mothers should be given guidance on the preparation for and maintenance of lactation, with special emphasis on the importance of the well-balanced diet both during pregnancy and after delivery. Unnecessary introduction of partial bottle feeding or other foods and drinks should be discouraged since it will have a negative effect on breast-feeding. Similarly mothers should be warned of the difficulty of reversing a decision not to breastfeed. Before advising a mother to use an infant formula, she should be advised of the social and financial implications of her decision. For example, if a baby is exclusively bottle-fed, more than one can (500g) per week will be needed, so the family circumstances and cost should be kept in mind. Mother should be reminded that breast milk is not only the best but also the most economical food for babies. If a decision to use infant formula is taken, it is important to give instruction on correct preparation methods, emphasizing that unboiled water, unsterilized bottles or incorrect dilution can lead to illness.

*See: International Code of Marketing of Breast Milk Substitutes, adopted by the World Health Assembly in Resolution WHA 34.22, May 1981.

Mothers should be explained the following advantages & nutritional superiority of breastfeeding:

  1. Immediately after delivery, breast milk is yellowish and sticky. This milk is called colostrum, which is secreted during the first week of delivery. Colostrum is more nutritious than mature milk because it contains more protein, more anti-infective properties which are of great importance for the infant's defence against dangerous neonatal infections. It also contains higher levels of, Vitamin 'A'.
  2. Breast miIk:
    1. Is, a complete and balanced food and provides all the nutrients needed by the infant (for the first six months of life).
    2. Has anti-infective properties that protect the infants from infection in the early months.
    3. Is always available.
    4. Needs no utensils or water (which might, carry germs) or fuel for its preparation.
  3. Breastfeeding is much cheaper than feeding infant milk substitutes as the cost of the extra food needed by the mother is negligible compared to the cost of feeding infant milk substitutes.
  4. Mothers who breast-feed usually have longer periods of infertility after child birth than non-lactators.

Details of management of breast feeding, as under:

  1. Breast-feeding.
    1. Immediately after delivery enables the contraction of the womb and helps the mother to regain her figure quickly.
    2. Is successful when the infant suckles frequently and the mother wanting to breast-feed is confident in her ability to do so.
  2. In order to promote and support breast-feeding the mother's natural desire to breast feed should always be encouraged by giving, where needed, practical advice and making sure that she has the support of her relatives.
  3. Adequate care for the breast and nipples should be taken during pregnancy.
  4. It is also necessary to put the infant to the breast as soon as possible after delivery.
  5. Let the mother and the infant stay together after the delivery, the mother and her infant should be allowed to stay together (in hospital, this is called "rooming-in").
  6. Give the infant colostrum as it is rich in many nutrients and anti-infective factors protecting the infants from infections during the few days of its birth.
  7. The practice of discarding colostrum and giving sugar water, honey water, butter or other concoctions instead of colostrum should be very strongly discouraged.
  8. Let the infants suckle on demand.
  9. Every effort should be made to breast-feed the infants whenever they cry.
  10. Mother should keep her body and clothes and that of the infant always neat and clean.
    Breast-feeding is the best form of nutrition for babies and provides many benefits to babies and mothers. It is important that, in preparation for and during breast-feeding, you eat a healthy, balanced diet. Combined breast and bottle feeding in the first weeks of life may reduce the supply of your own breast-milk, and reversing the decision not to breast-feed is difficult.
    Always consult your Health-care Professional for advice about feeding your baby. The social and financial implications of using infant formula should be considered. Improper use of an infant formula or inappropriate foods or feeding methods may present a health hazard. If you use infant formula, you should follow manufacturer's instructions for use carefully - failure to follow the instructions may make your baby ill.