Hypothyroid myopathy with manifestations of Hoffman's syndrome and myasthenia gravis.

Although hypothyroid myopathy is seen frequently and the relationship with autoimmune hypothyroidism and myasthenia gravis is well known, specific forms of hypothyroid myopathy such as Hoffman's syndrome (HS) are rarely described. Here we describe a 40-year-old patient with Hashimoto thyroiditis showing symptoms and signs of two discrete forms of hypothyroid myopathy (HS and myasthenic syndrome) together. To our knowledge this is the first reported case with features of both of these syndromes. We discuss the diagnosis, speculate whether this patient may represent a unique form of hypothyroid myopathy, and report the 6-month follow-up of the patient both clinically and electrophysiologically.