[Differential diagnosis of bilateral Ménière's disease and autoimmune inner ear disease].

Introduction

Ménière’s disease is an incurable, but manageable disease. The basis of its pathophysiology is the ‘enlargement’ of the endolymphatic space, which is called endolymphatic hydrops. It can be one- or two-sided, the latter is bilateral Ménière’s disease. Based on the time of the appearance of the symptoms, bilateral Ménière’s disease can be grouped into metachronous or synchronous groups. Autoimmune inner ear disease can present with similar symptoms.

Objective

Mapping of the inner ear of patients diagnosed with bilateral Ménière’s disease (7 patients: 2 men and 5 women), assessment of their immunological status, furthermore, differentiation from other pathologies, especially autoimmune inner ear disease, and creating an examination protocol based on experience. Method: Assessment of otolaryngological, otoneurological and immunological status and anamnesis in patients with bilateral Ménière’s disease during a symptom-free period. Assessment of the high- and low-frequency angular vestibulo-ocular reflex (aVOR). The former was detected with the video-head impulse test (vHIT), the latter with the calorization test. A pure-tone threshold audiogram and head magnetic resonance imaging were taken. Immunological laboratory test was performed from the patients’ blood serum.

Results

Systemic autoimmune disease was not confirmed in any of the patients. In all cases, bilateral pancochlear sensorineural hearing loss was shown, affecting the low frequencies, too. In two cases, we were able to detect lesions of high-frequency aVOR, which were considered progression of the disease. Bilateral canalparesis was visible in all cases during caloric reflex test. Discussion: Many studies in the literature deal with the discrepancy between vHIT and caloric reflex test. This was also observed by us. This may originate from the anatomy of the receptor of the aVOR, the crista ampullaris: while the high-frequency aVOR is detected by the centrally located type I hair cells, the low-frequency aVOR is detected by the peripherally located type II hair cells. Selective impairment of the latter was observed in both Ménière’s disease and autoimmune inner ear disease. It helped in the differentiation that the immunological status of the patients was in order, they reacted weakly to intravenous corticosteroid, and in one case improvement was found following a saccotomy.

Conclusion

Based on experiences, we attempted to propose an examination protocol in cases of patients who present with binaural symptoms and vertigo attacks. Among other things, it is recommended to carry out vHIT, caloric reflex test, and immunological examination. We also propose a multicenter study regarding both illnesses. Orv Hetil. 2024; 165(30): 1176–1183.