Adrenoleukodystrophy is transmitted as an X-linked trait (the neonatal form is by autosomal recessive transmission). Its incidence is estimated at 1 out of 20,000 to 1 in 50,000 and affects all races.
The metabolic defect is the accumulation of long chain fatty acids in the nervous system, adrenal gland, and testes, where the accumulated material disrupts normal activity. There are several (seven recognized) different forms of the disease.
The neonatal form appears shortly after birth and includes seizures and delayed neurological development with death occurring in infancy or young childhood. The childhood cerebral form (around 4-8 years) appears in mid-childhood, and the other forms appear during adolescence. About 33% of affected people develop neurological symptoms and about 50% develop abnormal adrenal function.
In the childhood form, early symptoms include hyperactivity, difficulty at school, difficulty understanding spoken material, deterioration of handwriting, crossed eyes (strabismus), and possibly seizures.
As the disease progresses, further signs of damage to the white matter of the brain appear and include changes in muscle tone, stiffness and contracture deformities, swallowing difficulties, and coma.
The other major component of the childhood form and all other forms of adrenoleukodystrophy is the development of impaired adrenal gland function (similar to Addison disease). There is a deficiency of steroid hormones. This is a very significant development but one that can be adequately treated with corticosteroids.
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