Hashimoto's encephalopathy presenting with musical hallucinosis

Neurological complications of thyroid disease are numerous and well known in the case of thyrotoxicosis or myxoedema,while the features of neurological involvement in Hashimoto’s thyroiditis have not been clearly characterised. Hashimoto’s encephalopathy (HE) is a severe and rare disorder, associated with Hashimoto’s thyroiditis, whose pathogenesis [2] is still debated, owing to the lack of specific markers of an autoimmune CNS involvement.At present its diagnosis simply relies on the detection of high titres of thyroid autoantibodies in serum, especially antimicrosomal antibodies, that are typical of Hashimoto’s thyroiditis. According to the literature, HE usually presents as vasculitic type or a diffuse progressive type with dementia, seizures, a psychorganic syndrome or altered consciousness, but atypical cases have been reported [2, 4].Here we describe the unusual case of a patient presenting after a long lasting episode of complex auditory hallucinosis with musical content, followed by behavioural abnormalities and cerebellar signs.