Patch testing for food-associated allergies in orofacial granulomatosis.

Food-associated allergies, especially to benzoates and cinnamon-related compounds, have been associated with orofacial granulomatosis and both standard and urticarial patch testing have been used to detect such allergies. Elimination diets have also been shown to be effective in some patients. To compare the results of standard and urticarial patch testing in a cohort of patients with orofacial granulomatosis. Records of 120 cases seen in two hospitals were retrieved and examined for patch test details. Standard patch testing was much less likely to detect allergy to benzoates and cinnamon compounds (7%) than urticarial tests (55%). All urticarial tests that were positive had shown a reaction by 60 min. Both standard and urticarial patch tests are required to detect food allergies in orofacial granulomatosis. The difficulties of patient self-recording of urticarial tests can be eliminated by retaining patients in the testing unit for professional reading of patches at 60 min.