頭部外傷後に発症したと考えられるadrenocorticotropic hormone(ACTH)単独欠損症の1例

Abstract

A 52-year-old male was admitted to our hospital with the complaints of general malaise, pretibial edema, speech disturbance, difficulty of grasping, hip joint pain, and calf myalgia. He had fallen from the roof of his house and had skull fracture and brain injury at 30 years old. After the accident, he had manifested general malaise and pretibial edema several times a year. Laboratory data on admission revealed high antidiuretic hormone secretion (0.9 pg/ml), in spite of low plasma sodium level (120 mEq/1) and low plasma osmotic pressure (255 mOsm/kg･H₂O). Then he was diagnosed as having syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Further endoclinological investigation revealed isolated adrenocorticotropic hormone (ACTH) deficiency low plasma cortisol. Intravenous administration of ACTH raised plasma cortisol level, and insulim-induced hypoglycemia made blunted response of ACTH. These finding's confirmed that he had isolated ACTH deficiency. The electroencephalogram revealed diffuse slow wave, and brain MRI showed normal pituitary gland. The electromyogram revealed the neurological pattern on right deltoid muscle, biceps brachii muscle, and triceps brachii muscle, and myogenic pattern on abductor digiti minimi muscle. Corticosteroid replacement therapy improved both clinical symptoms and manifestation of SIADH. This is a rare case of isolated ACTH deficiency with various kind of symptoms which occurred after head injury.