Milk Protein Allergy in Children (Cow's Milk Protein Intolerance, CMPA)

00:02 In this lecture, we’ll be discussing the intolerance of milk protein in formula.

00:09 So here’s an example.

00:11 A three-week old infant comes in with vomiting.

00:14 This three-week old is brought into her pediatrician and her mother says she’s been vomiting and her diapers have had blood in the stool.

00:22 When asked about the feedings, her mom says she’s been giving a cow’s milk based formula.

00:27 So, vomiting, diapers with some blood in the stool and a cow’s milk based formula, what do you suspect? The answer is milk protein allergy or milk protein intolerance.

00:41 But this isn’t really about milk.

00:44 This is about the intolerance of proteins found in milk.

00:49 So this in infants who are drinking milk.

00:52 That usually causes problems but not this one.

00:55 This is about the proteins that are found in milk and cow’s milk based formulas.

01:02 These proteins are basically prevalent in most basic formulas, and in fact, also prevalent in soy formulas, and that children who are allergic to cow’s milk based formulas may also be allergic to soy formulas.

01:19 So, let’s look at the different types of cow’s milk protein intolerance that exist in kids.

01:26 The first that we can talk about is usually after a year of age and is more commonly an IgE-mediated type 1 hypersensitivity reaction.

01:37 These children present with hives and wheeze as a result of exposure to milk proteins.

01:45 Another type is eosinophilic esophagitis and eosinophilic gastroenteritis.

01:52 This is an eosinophilic response to the milk protein that is occurring in the wall of the intestine, the wall of the stomach, and the wall of the esophagus.

02:02 This also happens usually a little bit later on.

02:06 In infants, the most common is the classic milk protein allergy, and this is a result of a cellular immune mediated type 4 hypersensitivity reaction.

02:21 I’m putting three and four together because there is a classic syndrome called food protein induced enterocolitis syndrome, which is given the initials FPIES.

02:34 And FPIES is this responds typically in small bowel, whereas, the milk protein allergy classically is in large bowel, but this is the same two entities; the FPIES is much more severe.

02:50 To remind you, the first type, which is the type 1 hypersensitivity reaction, is IgE mediated with rash and wheeze rather than bloody stools.

03:02 The second type is typically later in trial and presents with dysphagia and vomiting and abdominal pain rather than bloody stools.

03:11 And it’s this third and fourth type that will present as a classic process with blood in the stool and it is a cellular mediated process like a type 4 hypersensitivity reaction.

03:26 So let’s talk a little bit about classic milk protein allergy.

03:30 This is that last third and fourth group that we see in infants.

03:34 These infants present with blood in their stool.

03:38 They are usually otherwise healthy.

03:41 They may be a little bit fussy but they’re otherwise doing well, and this usually happens in the first few months of life.

03:49 FPIES is the very severe form that more often involves the small bowel.

03:54 These children present very early after they’re fed cow’s milk formula.

04:00 They have vomiting, bloody diarrhea, and abdominal distension.

04:04 And these children may have failure to gain weight.

04:07 They may have dehydration or they may rarely present in frank shock.

04:14 If we suspect milk protein induced enterocolitis, generally labs aren’t necessary.

04:19 This is mostly a historical and a physical exam diagnosis.

04:25 But on labs if you get them, you may see hypoalbuminemia from a decreased absorption of proteins.

04:32 You may see a leukocytosis, a general inflammatory reaction.

04:37 And of course, you will see heme-positive stools.

04:42 The diagnosis is typically made not based on labs but based on an empirical elimination diet followed by a food challenge.

04:51 So, let’s go through this.

04:53 A baby comes in with some blood in the stool, is otherwise well appearing.

04:57 First, we will eliminate milk protein from the diet.

05:00 Now, this seems pretty obvious for child with a milk protein allergy who is taking a milk protein based formula.

05:09 These infants will typically turn them and put them on an elemental formula such as Nutramigen, or Alimentum, which is very, very small groups of amino acids that are so small that in fact, they cannot form an allergen.

05:25 We will not put them onto soy formula because as you recall, about half of kids are also allergic to soy.

05:33 Then once they’re on this elimination diet, we’ll see if the symptoms resolve, and this typically takes a few days to a few weeks, and you should see the blood leave the stool.

05:45 One caveat I would add is that if the child is breastfed, it is effective to remove milk from the mother’s diet, and now the breast milk amazingly will reduce its likelihood of causing allergic symptoms.

05:59 So we don’t have to switch empirically breastfed children over to the Alimentum or the Nutramigen.

06:05 They may continue to breastfeed if the mother can be compliant with a milk-free diet.

06:11 At about a year of age, we will generally re-administer milk protein because this is a short-lived event of infancy.

06:18 And at that point, we’ll continue to see if symptoms follow.

06:21 If the child does well after that, that was classic for a simple milk protein allergy.

06:28 Formula-fed infants on a protein hydrolysate or amino-acid formula.

06:34 We are not going to switch them to soy milk.

06:37 I cannot emphasize that enough because the cross allergy is high.

06:41 This is especially too in FPIES.

06:44 In FPIES, a reintroduction of milk protein or soy protein which they may also be allergic to could be frankly dangerous.

06:54 In the treatment of FPIES in particular, remember that’s the very severe kind with the small bowel involvement, we will eliminate milk protein from the diet.

07:04 And infants with enterocolitis may need to be NPO with fluids because of the severity of their intestinal involvement before we reintroduce a more elemental formula.

07:18 So, blood in the stool in a baby.

07:23 In older children, this will present as wheeze and a rash.

07:27 In infants under one, this is a classic presentation of a simple milk protein allergy.

07:35 Most infants outgrow a simple milk protein allergy by the age of one, and milk proteins, cheese, yogurt, et cetera, may now be reintroduced into the diet.

07:46 FPIES or food protein induced enterocolitis syndrome is a severe cellular-mediated allergy involving more of the small bowel that must be handled very carefully.

08:00 And remember, elimination of milk protein from the diet, either through mother’s diet if she’s breastfeeding, or through introduction of an elemental formula is key to managing this problem.

08:13 Thanks for your attention.