A rare hereditary disease in which there is progressive degeneration of the white matter (myelin) of the brain and spinal cord, as well as impaired adrenal function. It occurs due to mutations that affect the metabolism of very long chain fatty acids, which leads to their accumulation and damage to myelin. It is manifested by cognitive impairment, movement disorders, adrenal insufficiency and behavioral changes. It most often affects men and requires specialized treatment.