Possible coconut allergy with facial rash
Question:
12/8/2023
While there is still little is known about this specific issue, here is an updated article on the subject.
Prevalence and burden of coconut allergy in the United States. Ann Allergy Asthma Immunol. 2023 Nov;131(5):645-654.e2. doi: 10.1016/j.anai.2023.08.017. Epub 2023 Aug 24.
https://pubmed.ncbi.nlm.nih.gov/37625503/
2/22/2022
An 8-month-old with a history of moderate-severe eczema, as well as few episodes of hives and facial swelling without obvious trigger. Had occurred after formula but not consistently (had switched from milk based to Alimentum) and after a coconut yogurt. Labs to milk IgE 0.19 and coconut IgE 2.26 (skin tests have been negative). Most infant formulas do have coconut oil listed as an ingredient - including Alimentum (modified coconut oil) - does this typically cause issues with coconut allergy?
Answer:
I am skeptical the patient is allergic to coconut with the specific-IgE 2.26 kU/L and a history of facial flushing or swelling or itching without ‘obvious trigger’. This opinion is based upon coconut not being a common food sensitizer, specific-IgE at the level detected not confirming coconut allergy, cutaneous reactions in infants with eczema being triggered by multiple factors and oils typically not containing significant amounts of protein or glycoprotein allergens. There are reports of coconut anaphylaxis, including 9 out of 5000 subjects evaluated for food allergy in Australia (1). The Australian group reported 26 less severe IgE-mediated coconut allergy. The authors concluded that “…coconut allergy is rare but real clinical entity, with a spectrum of severity that we have noted to include striking cases of anaphylaxis.”
Coconut water contains 30% or less protein than coconut milk. Thus, I would consider a food challenge with coconut water to verify if the infant is allergic to coconut. Depending on the comfort level of you and the parents, you could start with diluted coconut water or a minimal amount, for example 0.1-0.5 ml, and double or quadruple the amount every 20-30 minutes. If the child passes the challenge, then I do not think you need to be concerned about coconut oil or other coconut products.
1. Pathmanandavel, Karrnan, et al. "Anaphylaxis and allergy to coconut: an Australian pediatric case series." The Journal of Allergy and Clinical Immunology: In Practice 8.10 (2020): 3657-3659.
I hope this information is of help to you and your practice.
All my best.
Dennis K. Ledford, MD, FAAAAI