NOT ALL RASHES ASSOCIATED WITH INFANT FEEDING ARE FROM COW MILK PROTEIN ALLERGY!

Abstract

<h3>Introduction</h3> Cow's milk protein allergy (CMPA) is the most common food allergy in the infancy period. The prevalence of CMPA in the United States has been increasing rapidly over the last decade. CMPA can be IgE-mediated or non-IgE-mediated. Non-IgE mediated reactions are often difficult to diagnose as there is no substantiative test. Many diagnoses of non-IgE mediated reactions are thus unconfirmed and may be incorrect. Facial rashes could occur because of other disorders too. <h3>Case Description</h3> Our patient is a 4-month-old infant, who presented with a facial rash that sometimes spread to the torso after feeds. The patient was born at term via prolonged vaginal delivery due to facial presentation. He was breastfed until two months, then switched to formula due to colic. Subsequently, the mother noticed a facial rash with feeds that resolved quickly without intervention. He was tried on different formulae, but the symptoms persisted. Upon admission, he was noted to develop facial flushing on the cheeks and forehead even with Pedialyte administration, along the distribution of the auriculotemporal nerve. Laboratory investigations (CBC, IgE for milk and soy, tryptase) were within normal limits. <h3>Discussion</h3> The infant was suspected immediately of having CMPA, but the presentation was inconsistent with an allergic reaction (absence of hives, itching, discomfort, other system involvement, and quick resolution without intervention). On the contrary, he developed flushing even with Pedialyte, which was more suggestive of a nervous system-related phenomenon, such as Frey's syndrome. He was transitioned back to cow milk-based formula, and the facial flushing improved over time.