Hoffmann syndrome; a rare form of hypothyroid myopathy

Abstract

Hoffman syndrome is a rare clinical presentation characterized by the presence of proximal weakness and muscle pseudo-hypertrophy in a hypothyroid patient. 50-year-old male presented with gradual onset muscle stiffness and weakness involving both bilateral upper and lower limbs for 3-months duration. Examination revealed generalized hypertrophy of the muscles, mainly involving the Gastrocnemius with proximal muscle weakness and slow relaxing deep tendon reflexes. His Thyroid Stimulating Hormone and creatinine kinase were elevated. Anti-Thyroid peroxidase antibodies were positive. Electromyogram (EMG) and muscle biopsy was suggestive of a myopathic disorder and a diagnosis of Hoffmann syndrome was made. Complete resolution of weakness was observed following thyroxine therapy. Hoffmann syndrome is a rare, myopathic disorder seen in long standing, untreated hypothyroidism and it has a favourable response to thyroid hormone replacement in majority of patients.

Hoffman’s syndrome-a rare neurological presentation of hypothyroid myopathy

“…The muscle involvement in hypothyroidism is caused by changes in muscle fibers from fast-twitching type II to slow-twitching type-I fibers which results in slowness of muscle contraction associated with hypothyroidism. 3,4 The cause of hypertrophy may be due to an increase in connective tissue and increase in size and number of muscular fibers. Pseudo hypertrophy of muscles is characteristic feature of Hoffman's syndrome which is due to deposition of glycosaminoglycans.…”