Cow’s Milk Protein Allergy in Infants Under One Year

In my outpatient practice, this is the most common cause of blood in the stool in infants under one year.

Usually, a mother comes in because her baby has had a bowel movement and she noticed isolated streaks of blood in the stool. The stool may be loose, but it is generally the baby’s usual stool: mushy, rarely firm, and unchanged in color.

On questioning and examination, the baby is active, gaining weight appropriately, has a normal appetite, has not had a fever, is not kicking or crying, and the abdomen is soft and non-tender on palpation. In other words, the condition is not bothering the baby. A more detailed history may reveal, if the mother is breastfeeding, that the day before she drank milk or coffee with milk, ate beef, or had other dairy products.

Sometimes, it turns out that there have been previous episodes of blood streaks in the stool.

Blood in the stool can also occur in formula-fed babies, so we ask which formula the baby is receiving.

This clinical picture is consistent with CMPA.

If the mother is breastfeeding, we will need to recommend a diet for her (one of the rare situations in which a mother really does need a diet).

The diet involves removing whole milk, dairy products, and beef from the mother’s diet. It is important for her to check the ingredients in packaged foods: cookies, muffins, and similar products can also contain traces of milk. I once saw a mother who said she was following a dairy-free diet, but further questioning revealed that she drank coffee with milk every morning.

After 4 weeks on a strict diet, we assess the baby’s condition. If the blood streaks persist, the next food we remove is egg (importantly, milk is not reintroduced). After another 4 weeks, we reassess. If the streaks still persist, we remove soy; if symptoms continue after a further 4 weeks, we remove corn.

Cow’s milk is the most common trigger for CMPA (about 76%), but food protein allergy can also be triggered by egg (16%), soy (6%), and corn (2%).

We can exclude all four foods at once; however, it is important that the mother also feels comfortable, because following a strict diet is exhausting.

The diet is followed for at least 6 months, but usually for 12–18 months.

When complementary foods are introduced, the same recommendations apply to the baby.

Once the blood streaks have disappeared and the child has reached 1–1.5 years of age (at this age, intestinal permeability is lower and proteins do not pass through the intestinal barrier as easily), or earlier if the doctor and family jointly decide that the child is ready to reintroduce these foods, we begin reintroducing dairy into the mother’s diet (if breastfeeding continues) and the child’s diet using the milk ladder.

There are different milk ladders. Together with your doctor, choose the one that is most suitable for you. I will publish the most popular version; there are also 12-step ladders that reintroduce milk more slowly.

What should be done if the baby is formula-fed?

Initially, a baby will generally receive a standard infant formula containing cow’s milk protein, which, as we have already established, is the main trigger for CMPA.

• When the clinical picture is consistent with CMPA, we have to change the formula.
• We initially prescribe an extensively hydrolyzed formula (for example, Alfaré, Nutrilon Pepti Gastro, Pepticate, Nutrilak Peptidi MCT, or Frisopep).
• After introducing the new formula, we monitor the symptoms for 1–2 weeks.
• If the blood streaks persist, we switch to an amino acid formula (for example, Nutrilon Amino Acids, Alfaré Amino, or Neocate LCP).
• Continue the appropriate formula until the child turns one.
• After one year, we begin switching to another formula. If the child was receiving an amino acid formula, we switch to an extensively hydrolyzed formula for 1–2 months. If the child was receiving an extensively hydrolyzed formula, we switch to a moderately hydrolyzed, hypoallergenic formula (for example, NAN Hypoallergenic, Nutrilon Hypoallergenic, Similac Hypoallergenic, or Nutrilak Premium Hypoallergenic), also for 1–2 months. After introducing the hypoallergenic formula, we introduce fermented dairy products and then switch to a standard infant formula.
• The transition to a new formula is gradual: at each feeding, replace 30 ml of the previous formula with the new formula.

Additional material from the document: the iMAP Milk Ladder

The iMAP Milk Ladder is intended for children with mild to moderate non-IgE-mediated cow’s milk allergy. It must be used under a doctor’s supervision.

Step 1. Cookie or sponge cake

Start with 1 cookie or piece of sponge cake and gradually increase the amount to 3 pieces.

Step 2. Muffin

Start with 1/2 a muffin and gradually increase the amount to a full portion.

Step 3. Pancake

Start with 1/2 a pancake and gradually increase the amount to a full portion.

Step 4. Cheese

Amount: 15 g of hard cheese or Parmesan.

Step 5. Yogurt

Amount: 125 ml.

Step 6. Pasteurized milk or standard infant formula

Start with 100 ml. If well tolerated, gradually increase the volume to 200 ml.
At each step, you can begin with 1/2–1/4 of the portion and gradually work up to a full portion over several days. For the lower steps, homemade foods are recommended so that you know exactly how much milk is being consumed. Moving from one step to the next must be agreed with your doctor.