Clinically relevant patch test results in patients with burning mouth syndrome

Background: Patients with a sore or burning mouth associated with clinically normal oral mucosa present a difficult diagnostic challenge. Objective: The objective of this study was to assess the value of patch testing in patients with burning mouth syndrome. Methods: We retrospectively reviewed the results of patch testing to an oral series in patients with burning mouth syndrome seen at Mayo Clinic, Rochester, Minnesota, between January 2000 and April 2006. Results: Of 195 consecutive patients with a burning or sore mouth, 75 had patch testing to an oral series, and 28 of these patients (37.3%) had allergic patch test reactions. The most common allergens were nickel sulfate hexahydrate 2.5%, balsam of Peru, and gold sodium thiosulfate 0.5%. On follow-up, 15 patients reported improvement, 4 removed or avoided the offending dental metal, and 6 avoided the dietary allergen. Thirteen patients did not improve; 6 avoided identified allergens, but without improvement; 1 removed dental metals without symptom change; and 5 avoided test-positive dietary allergens but without improvement. The remaining 7 nonresponders had nonrelevant patch test results or did not avoid allergens. Conclusions: Patch testing can identify patients who may be allergic to dental metals or dietary additives and who may benefit from removal or avoidance of these.