The value of mucosal allergen challenge for the diagnosis of food allergy.

PURPOSE OF REVIEW: The incidence of food allergy is increasing. Correct diagnosis is dependent on food challenges, which are not always performed, but more often based on history, skin prick test and specific IgE, leading to possible misdiagnoses. Mucosal provocation tests have been proposed as possible new diagnostic tools during recent decades.

RECENT FINDINGS: The databases EMBASE, PUBMED and Cochraine Review were used. Seven full text articles fulfilled criteria for mucosal challenge and food allergy, only one from the last 12 months. Conjunctival, nasal, buccal, gastric and coecal/rectal mucosa have been challenged. All authors find mucosal changes after challenge, but the lack of validation against double-blind placebo-controlled challenges makes evaluation difficult, with the exception of the conjunctival provocation test.

SUMMARY: As most mucosal surfaces are easily available, and small amounts of allergen are needed for an obvious reaction, this tool for diagnosing food allergy is promising. Further studies are however needed.