Adrenoleukodystrophy, Autosomal

Patient Information

Characteristics

Background and History

This is one of a rather large number of enzymatic disorders of fat metabolism that results in the accumulation of material in cells which cause damage, in this case, of nerve cells and those of the adrenal gland.

Clinical Correlations

This type of adrenoleukodystrophy (NALD) is often diagnosed at birth from the occurrence of seizures and evidence of mental deficits. Other signs are a high forehead, low-set ears, abnormal folds in the eyelids and crossing of the eyes. Some infants have cataracts and unusual pigmentation of the retinas has been observed. The roof of the mouth (hard palate) is often highly arched. Damage to the adrenal glands may produce increased pigmentation of the skin as early as 3 months of age. Cysts in the kidney may occur. By one year of age there is usually evidence of psychomotor regression and the rapid progression of neurological disease may lead to death by 3 years of age.

Genetics

Inheritance

Based on the rare patients reported, this disorder follows an autosomal recessive pattern of inheritance in which two copies of the mutation must be present. Parents do not have disease but are carriers of a single mutation and they can expect that one in four of their children on average will inherit both copies and have NALD.

Pedigree

Autosomal recessive

In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.

Diagnosis and Prognosis

The diagnosis is usually made by a team of pediatricians, neurologists, medical geneticists and ophthalmologists based upon clinical examination with blood and hormone studies. The disease is relentlessly progressive and early death is common.

There is no cure for the gene defect but supportive care and monitoring are important.