Systemic Reaction to an Extensively Hydrolyzed Formula in an Infant with Cow’s Milk Anaphylaxis
Alvaro FloresMD1 and Yudy K. Persaud. MD, MPH2
  1. Division of Pediatric Gastroenterology, Hepatology and Nutrition, University of Nebraska and Children’s Hospital & Medical Center, Omaha, NE
  2. Division of Allergy, BronxCare Health Systems. Bronx, NY
Corresponding Author:
Yudy K. Persaud MD/MPH
Division of Allergy, Asthma & Immunology
BronxCare Hospital Systems
1650 Selwyn Ave, Bronx NY
ypersaud@bronxcare.org
7185901800(hospital)
7186799779 (fax)
Funding source: There was no funding source for this manuscript
Dr. Flores has no relevant disclosures to declare
Dr. Persaud has received an honorarium for serving on the advisory board and speakers bureau for GlaxoSmithKline(GSK). He also participates in research with Astra Zeneca that is unrelated to this article.
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.

Keywords: Cow’s milk, allergy, anaphylaxis, B-lactoglobulin, extensively hydrolyzed formula.