Case Report
Our patient is a three-month old full-term male with an unremarkable past medical history. He presented with anaphylaxis after being fed cow’s milk formula for the first time. He was exclusively breastfed since birth but an initial trial of regular cow’s milk formula led to a severe allergic reaction. Within 30 minutes after introducing cow’s milk he had an episode of vomiting followed by wheezing, stridor and bilateral eyelid and lip swelling. Treatment included injection of intramuscular epinephrine and further emergency medical services. In the emergency room, vital signs were stable (blood pressure (83/63), heart rate (153), respiratory rate (48), and an oxygen saturation (100%). His physical exam was remarkable for diffuse urticarial rash and bilateral eyelid swelling. Subsequently, he was treated with oral prednisolone, diphenhydramine, ranitidine, given a normal saline bolus and was admitted to pediatric intensive care for anaphylaxis monitoring. Laboratory evaluations were as follows: total immunoglobulin E (IgE)23 kU/L, IgE to cow’s milk: 1.64 kU/L, soybean igE <0.1 kU/L, alpha-lactalbumin: 1.73 kU/L, Beta-lactoglobulin: 3.73 kU/L, casein: 2.58 kU/L:. An oral challenge with soymilk was attempted but the patient developed acute right eyelid edema and urticarial rash. He was then trialed on extensively hydrolyzed formula but unfortunately developed immediate angioedema and diffuse urticaria. His condition was suggestive of an type 1 hypersensitivity phenomena requiring further management in the intensive care unit. Eventually, an amino acid-based formula was given and was well tolerated without any further reactions. He was discharged with an EpiPen and amino acid-based formula and was followed by the allergy team as an outpatient.
Our patient presented with signs and symptoms consistent with anaphylaxis and was appropriately treated with intramuscular epinephrine which is the single most effective treatment for anaphylaxis.(6) Oral steroids and antihistamines were given as adjuvant therapy in the management of the anaphylactic symptoms[6].
The standard for the diagnosis of IgE mediated food allergies is a blinded oral challenge test, but when the presentation is consistent with a severe allergic reaction or anaphylaxis, the diagnosis can be confirmed with a positive IgE test in the blood or a skin prick test [8]. In our case the etiology was confirmed via an IgE test to milk and its components. However, an oral trial with soy and an extensively hydrolyzed formula proved unsuccessful.