Systemic Reaction to an Extensively Hydrolyzed Formula in an Infant with
Cow's Milk Anaphylaxis
Background: Cow´s milk allergy is the most common cause of food allergy
in young children. Ingestion of milk products in children with a milk
protein allergy can lead to anaphylaxis and must be avoided. Most
guidelines generally recommend the use of an extensively hydrolyzed
formula (EHF) in these cases; however rare allergic reactions can still
occur. Here, we present a 3-month-old who developed anaphylaxis to a
cow’s milk formula. Subsequently he developed a rare systemic reaction
to soy and an extensively hydrolyzed formula. Case: The patient had an
unremarkable past medical history and presented with signs and symptoms
consistent with anaphylaxis after being fed cow’s milk formula for the
first time. Symptoms included immediate vomiting, wheezing, stridor,
angioedema of eyelids and lips. Although IM epinephrine was given, the
patient continued to clinically deteriorate becoming more lethargic and
necessitating admission to the pediatric intensive care unit.
Subsequently, a trial of soy formula ingestion reproduced similar
symptoms and an EHF was given. However immediately after taking an EHF,
he developed facial angioedema and diffuse urticarial lesions.
Conclusion: In most cases with a cow’s milk allergy, an extensively
based formula can be tolerated safely due to a hydrolyzed protein chain.
However, medical providers must be vigilant when switching formula since
a rare systemic allergic reaction to EHF can still occur.