Cow’s Milk Protein Allergy or FPIES: Which One Is It?
Cracking the Code: Is It Cow's Milk Protein Allergy or FPIES? Here's How to Tell
Updated November 10, 2024.
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One worry that keeps many parents awake at night is the thought of their child developing a food allergy. If their toddler enjoys pizza and cake at a birthday party, will he suddenly become gravely ill? Listening to stories from friends and family members, it may seem as if allergies to milk and other foods are very common. In reality, only four percent of kids worldwide experience such reactions.
Parents may feel even more anxious when doctors use funny-sounding acronyms. For example, they may be told their daughter has something called FPIES after a severe reaction to avocados. All of this can be confusing and overwhelming, but it need not be.
Let’s discuss two common types of allergies to cow’s milk, and distinguish them from food protein-induced enterocolitis.
Cow’s Milk Protein Allergy: Two Types of Reactions
Cow’s milk and dairy products are components of much of the world’s diet. In addition to being a recommended source of calcium and vitamin D, cow’s milk is a key ingredient of most infant formulas. When an allergic reaction occurs, it is due to the casein or whey proteins. One type of reaction is associated with irritation of the gastrointestinal tract, and the other is the result of an antibody response.
Food Protein-induced Allergic Proctocolitis (FPIAP)
A newborn baby boy has been breastfeeding without difficulty since leaving the hospital. At two weeks old, his mother notices that he seems fussy after feedings, and is difficult to console for naps or bedtime. The following week, while changing his diaper, mom notices mucous and red “streaks” mixed into his stool.
Each stool thereafter has the same abnormal color, so she schedules an appointment with his pediatrician. After examining the baby and testing his stool, it is discovered that the red “streaks” are blood. Mom is informed that her son has a type of cow’s milk protein allergy known as FPIAP.
The type of cow’s milk protein allergy in this scenario is called food protein-induced allergic proctocolitis. Because this is a “mouthful” to say, it is referred to as FPIAP. This condition is associated with inflammation of the inner lining of colon, the part of the gastrointestinal tract where stool forms. As food waste travels through the colon, undigested milk proteins cause irritation and small amounts of bleeding. As a result, blood and mucous are passed with stool, and later detected in a soiled diaper.
Infants who have FPIAP may experience fussiness and feeding difficulties due to stomach pain. In severe cases, these babies may have difficulty gaining weight.
Important Points to Know About FPIAP:
1. Symptoms appear within the first month of life.
2. FPIAP is seen in breastfed infants if dairy is a part of a mother’s diet, and among infants who drink a cow’s milk-based formula
3. 50 percent of infants with a cow’s milk protein allergy are also allergic to soy.
4. Most babies outgrow FPIAP by their first birthday.
If FPIAP is suspected, it is important to schedule a visit with your healthcare provider. The diagnosis is made based on symptoms. If it is unclear whether or not blood is present in the stool, an in-office test can be performed as a confirmation.
What Can Parents Feed a Baby Who Has FPIAP?
The primary feeding goal is to avoid exposure to cow’s milk protein, and allow the inflammation within colon to heal. The bloody stools and discomfort typically resolve within two weeks. Mothers who are able to eliminate dairy from their diets can continue to breastfeed. Formula fed infants are switched to a hydrolyzed formula.
The primary feeding goal is to avoid exposure to cow's milk protein and allow the inflammation within the colon to heal
This means that the cow’s milk proteins are broken down into smaller particles during the manufacturing process, and are less likely to cause inflammation. Babies who are very sensitive may require an extensively hydrolyzed infant formula in which the proteins are processed down to their basic amino acids. After age six months when foods are introduced, those with dairy are avoided. By age 12 months, most infants are able tolerate cheese, yogurt, and milk, but some toddlers remain allergic until age two.
IgE-Mediated Cow’s Milk Protein Allergy
Maya has a known cow’s milk protein allergy, and attends preschool. To prevent accidental exposures, her parents provide a lunch from home for her to eat at school. On the day of a classmate’s birthday celebration, her mom includes a dairy-free cupcake in her lunchbox. Maya’s eats this cupcake while her best friend sits next to her, enjoying ice cream. With melted ice cream on her hand, the friend reaches over to playfully grab Maya’s arm. Immediately, the arm becomes red and swollen. A rash then begins to spread to other areas of her body. Fortunately, Maya’s teachers react quickly as they have been provided with an allergy plan, and an injectable medication in case of an allergic reaction to milk.
In this scenario, skin contact with cow’s milk protein triggered an immune response. A similar and likely more severe reaction would occur if Maya had eaten some of the ice cream. Exposure to this allergen causes the immune system to increase the amount of IgE antibodies circulating in the bloodstream.
This is the same antibody associated with other food allergies as well as those to bee stings or plant pollens. As IgE attaches to histamine-releasing cells on organs throughout the body, symptoms of the allergic reaction worsen.
Key points about IgE-mediated cow’s milk allergies:
1. Infants may have no symptoms when breastfed or formula fed for several months. Sensitivity to cow’s milk protein develops over time and with continued ingestion.
2. Allergic reactions may not appear until yogurt, cheese and other dairy are introduced into the diet.
3. Symptoms can progress rapidly and become severe within minutes.
Multiple organs of the body may be affected when an IgE-mediated reaction occurs. Symptoms may appear on:
• Skin: hives, swelling, eczema
• Gastrointestinal tract: vomiting, stomach pain, diarrhea
• Lungs, bronchial airways: wheezing, difficulty breathing
• Mouth: swelling of lips, tongue or throat
• Cardiovascular system: low blood pressure, shock
When allergic reactions affect more than just the skin, it is called anaphylaxis. This situation can be life-threatening, and requires immediate medical attention.
How to Know If Your Child Has an IgE-Mediated Cow’s Milk Protein Allergy?
Most cases of IgE-mediated cow’s milk protein allergy are diagnosed based on symptoms and subsequent testing. Skin prick tests produce swelling and redness when a minuscule amount of milk protein is applied to the skin. Food “allergy panel” blood tests can detect milk allergies, but may be less accurate than skin tests. Allergy specialists often do “milk challenge” tests which involve drinking a small amount of milk in an office setting where reactions can be easily managed.
Prevention and Management of Allergic Reactions
When an IgE-mediated cow’s milk allergy is suspected or confirmed, avoidance of cow’s milk is the first line of treatment. Options include:
• Hydrolyzed or extensively hydrolyzed infant formula
• Eliminating dairy from a mother’s diet if breastfeeding
• Avoiding cow’s milk, cheese, yogurt, and other dairy products
This can create a dilemma during the toddler years. At age 12 months, the American Academy of Pediatrics recommends introducing whole cow’s milk due to its higher fat content. For those with a cow’s milk protein allergy, soy milk is their recommended alternative. However, it is common for these kids to also have a soy allergy. A plant-based beverage made with almonds and buckwheat may be a better alternative.
Because IgE-mediated reactions can be severe, it is important to have certain life-saving medications at home and school. These include:
• Oral antihistamines: Medications such as diphenhydramine and cetirizine can reduce or stop mild symptoms. These are most effective when only a rash or hives are present.
• Injectable epinephrine devices: If vomiting, difficulty breathing, facial swelling or other symptoms develop, epinephrine prevents further progression of the allergic reaction.
• Oral steroids: These medications may be administered in addition to anti-histamines or epinephrine to prevent the recurrence of “rebound” symptoms hours later.
For daycare or school attendance, a written allergy plan may be requested in case of an accidental exposure to cow’s milk. Life-saving medications may also be kept at school.
Some children outgrow this type of cow’s milk allergy, often by age four. For persistent cases, oral milk desensitization therapies are currently available for children ages 6 and older to help build tolerance. This type of treatment can reduce the likelihood of anaphylaxis after an unintended exposure, or enable the child to eat small amounts of dairy without a reaction.
Food Protein-Induced Enterocolitis Syndrome (FPIES)
FPIES is the acronym for food protein-induced enterocolitis syndrome. A few of its characteristics are similar to FPIAP. For example, FPIES is not associated with an IgE antibody response, and involves the gastrointestinal tract. However, there are significant differences. FPIES may develop during infancy, childhood, or adulthood. It can be caused by any type of food, not just cow’s milk. It is also less common than FPIAP, only affecting 0.5% of children in the U.S.
After Ashley’s 6 month old office visit, her mom is excited to start offering foods. She purchases a box of infant oat cereal, and sweet potatoes to cook, purée, and freeze. Remembering that only one food should be offered at a time, she prepares a bowl of oat cereal mixed with infant formula for “dinner.” With the first spoonfuls, Ashley frowns, but then eagerly finishes the cereal. Feeling full, she sleeps through the night. The following evening, mom gives Ashley her second try of oat cereal. Both the meal and bedtime routine go well.
At 11pm, however, Ashley suddenly wakes crying, and begins to vomit. As mom attends to her, she vomits again and again. Very concerned, mom takes her to the local emergency room. By the time they arrive, Ashley has developed diarrhea and looks lethargic. She is admitted to the hospital for IV fluids and further evaluation.
Looking much better by the next afternoon, mom tries feeding oat cereal again. A few hours later, the vomiting resumes. After consultation with the hospital’s pediatric gastroenterologist and allergist, it is determined that Ashley has FPIES.
What Exactly Is FPIES?
Food protein-induced enterocolitis (FPIES) is an inflammation of both the small intestines and colon in response to a food. Healthcare providers use specific criteria to determine whether or not a child has this type of food allergy:
Major criteria:
Vomiting within 1 to 4 hours of eating the offending food
No increase in IgE antibodies
Minor criteria:
More than 2 episodes of vomiting
Lethargy
Diarrhea within 5 to 10 hours
Need for ER evaluation and IV fluids
Low blood pressure
Low body temperature
FPIES symptoms are severe, and can appear life-threatening. Infants may show symptoms as young as two to three months old. However, this type of allergic reaction may develop at anytime during a child’s life.
What Foods Cause Food Protein-induced Enterocolitis Syndrome?
Any food can cause FPIES. Cow’s milk, soy, and oats are the most common triggers prior to age 6 months. Foods that are more likely to cause symptoms among older infants and children include:
- Rice
- Eggs
- Fish
- Nuts
- Meats
- Carrots
- Sweet potatoes
- Avocado
- Apples
- Bananas
The most severe symptoms occur after ingesting rice. Formula fed infants are at a higher risk of developing FPIES. After multiple episodes, weight gain and growth may be impaired.
How Do I Know If My Child Has FPIES?
The diagnosis is typically made based on a history of eating a food, then having symptoms that fit the established criteria. Because of the symptom severity, most infants and children are hospitalized for fluid replacement, and to stabilize their blood pressure and temperature. Doing a food challenge in a hospital setting while monitoring for symptoms can help to determine which foods are problematic.
Dietary Management of FPIES
The mainstay of treatment is eliminating the identified food triggers from the child’s diet. There is also a protocol for infants who have not yet begun to eat foods.
Prior to food introduction: It is recommended that breastfeeding mothers avoid cow’s milk and soy in their diets. Formula fed infants are given hydrolyzed or extensively hydrolyzed infant formulas.
After food introduction: All foods are discontinued for 2 to 4 weeks, and infants resume exclusive breastfeeding or a hydrolyzed infant formula. This allows time for the intestinal inflammation to improve. Foods are then re-introduced one at a time in order to determine which has caused the allergic reaction.
After being hospitalized, most infants and children receive follow up care from a pediatric gastroenterologist. In clinical practice, I have seen cases of FPIES resolve after six to 12 months of avoiding the problematic food. After this time period, this food may be slowly re-introduced into the child’s diet. Eventually, most children will be able to resume eating it without further allergic reactions.
Now That You Know the Terminology…
Food allergies now have more descriptive names: IgE-mediated cow’s milk protein allergy, FPIAP, an FPIES. Each one has different symptoms, and recommendations to prevent further allergic reactions. If you believe your infant or child has one of these food allergies, discuss the symptoms with your pediatrician or family healthcare provider. In some cases, the assistance of a pediatric allergist or gastroenterologist may be necessary. What is most important is that you are aware of the symptoms, and have a plan of action.
The content and advice provided in this article are for informational purposes only and are not a substitute for medical diagnosis, treatment, or advice for specific medical conditions. Always consult a pediatrician to understand the individual needs of your child.
References
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