Background: Recurrent aphthous stomatitis (RAS) is a common disease of the oral mucosa with an unknown etiology. This study aimed to determine if food additives play a role in the etiology of RAS as well as to determine if patch testing can be used to detect which allergens cause RAS.
Methods: This prospective study included 24 patients with RAS and 22 healthy controls. All the participants underwent patch testing for 23 food additives.
Results: In total, 21 (87.5%) RAS patients and 3 (13.6%) controls had positive patch test reactions to ≥1 allergens; the difference in the patch test positivity rate between groups was significant (P < 0.05). The most common allergen that elicited positive patch test results in the patient group was cochineal red (n = 15 [62.5%]), followed by azorubine (n = 11 [45.8%]) and amaranth (n = 6 [25%]).
Conclusions: The present findings show that food additives might play a role in the etiology of RAS and that patch testing could be a method for determining the etiology of RAS.
© 2016 The International Society of Dermatology.