Skin test, RAST and clinical reactions to peanut allergens in children.

One-hundred-and-four children were skin-tested with four peanut-allergen preparations, a commercial extract, extracts of raw and roast peanuts prepared by NH4HCO3 extraction, and a wheatgerm lectin-reactive glycoprotein obtained by affinity chromatography. The presence of symptoms after ingestion of peanut or peanut products was also recorded. The roast allergen extract provided the greatest specificity with eight symptomatic children having a positive skin test and only one positive skin-test reaction in an asymptomatic child in the group of 104 children tested. Despite differences in the incidence of skin-test reactions there was a strong correlation between raw, roast and commercial RAST suggesting common allergens were being identified by circulating IgE. Clinical sensitivity was observed particularly in younger children with 75% of the children being under 4 years of age. A positive roast skin test or a RAST test adds confirmation to the clinical history of allergic reactions to peanuts.