Provocation of endolymphatic hydrops with a prick test in Meniere's disease

This study was conducted to test the hypothesis that antigenic challenge is an important stimulative factor for an episode of endolymphatic hydrops. The study was held in a tertiary care center for patients with probable or definite Meniere's disease. The prick test, which included dietary and inhalant allergens, was applied to all patients with a Multi-Test Applicator (Lincoln Diagnostics, Decatur, Ill). Patients were tested with electrocochleography before and after the prick test. The positive allergen was diluted in 1/10 of a prick test dose, and patients were provoked and tested again. A negative summating potential/action potential (SP/AP) amplitude ratio greater than 0.5 was used as the main outcome measure. Pretest, posttest, and postprovocation SP/AP amplitude ratios were compared. A total of 80 diseased and 16 normal ears of 48 patients with Meniere's disease were assessed. All patients were found to be atopic, but none had allergic symptoms. No symptom like vertigo or fullness was seen after the prick test was performed. In all, 30 patients had tinnitus and fullness in the diseased ear, and 6 patients had vertigo after the provocation. The SP/AP ratio was greater than 0.50 in 23 diseased (29%) and 3 normal (19%) ears before the prick test. After the prick test, 62 diseased (78%) and 13 normal (81%) ears had endolymphatic hydrops. These numbers did not change much after the provocation. Results reported here support the role of antigenic stimulation for episodes of Meniere's disease. Endolymphatic hydrops was the atopic reaction that occurred in most study patients.