[A case of hypothyroidism associated with hypokalemic periodic paralysis]

A case of hypothyroidism associated with hypokalemic periodic paralysis was reported. The patient, a 50 year-old female was admitted because of recurrent paralytic attacks. She had not presented any symptoms of hypothyroidism. Physical examination on admission revealed muscle weakness of limbs, but not enlargement of thyroid glands. Paralytic attack was induced by oral intake of 100 g of glucose, and during attacks, serum K levels ranged from 3.4 to 3.0 mEq/l. She was diagnosed chronic thyroiditis by the high level of TSH and thyroid related anti-antibodies in the serum. Muscle biopsy showed type II atrophy. After the improvement of thyroid function, her paralytic attack disappeared. Present study suggested that hypothyroidism could be a cause of hypokalemic periodic paralysis. This case was very rare and seemed important in etiology of periodic paralysis.