A Rare Cause of Sudden Hearing Loss: Neurosarcoidosis

Abstract

arcoidosis is an inflammatory disease with multi-systemic involvement. Symptoms related with the central nervous system occur in approximately 5-7% of patients with sarcoidosis which in that case the clinical picture is called neurosarcoidosis (NS). 1 In 80% of NS cases the most common symptom is cranial neuropathy, especially facial and optic nerve neuropathy. 1-3 The involvement of the vestibulocochlear nerve occurs in 1-7% of NS patients. 1,2,4,5 The histopathological correlation of audiovestibular dysfunction in NS was first described with the autopsy findings in a deaf NS patient in 1984. 6 Researchers observed perivascular lymphocytic infiltration resulting with significant axonal degeneration and demyelization especially in the acoustic, vestibular and facial nerves. The hearing loss and vestibular dysfunction in sarcoidosis were thought to be reversible initially. However in some patients it is thought that, irreversible damage occurrs as a result of the ischemic process secondary to vasculitis. 6