Adrenoleukodystrophy (ALD) refers to several different inherited conditions that affect the nervous system and adrenal glands. Other names for it are adrenomyeloneuropathy, childhood cerebral ALD, and Schilder-Addison Complex. The gene that causes ALD was identified in 1993. It occurs in about 1 in 20,000 people and mainly affects men. Women can carry ALD without having any symptoms. The symptoms, treatments, and prognosis of ALD vary depending on which type is present. ALD is not curable, but the progression can be slowed in some cases.
The genetic bases for all different phenotypic variants of X-ALD are mutations in the gene encoding the peroxisomal ATP-binding cassette (ABC) transporter, ABCD1 (formerly adrenoleukodystrophy protein, ALDP). ABCD1 transports CoA-activated very long-chain fatty acids from the cytosol into the peroxisome for degradation. The phenotypic variability is remarkable ranging from cerebral inflammatory demyelination of childhood onset, leading to death within a few years, to adults remaining pre-symptomatic through more than five decades. There is no general genotype-phenotype correlation in X-ALD.Treatment methods depend on the type of ALD. Steroids can be used to treat Addison’s disease. switching to a diet that contains low levels of VLCFAs, taking Lorenzo’s oil to help lower elevated VLCFA levels, medications to relieve symptoms such as seizures, physical therapy to loosen muscles and reduce spasms
X-ALD is considered by many to be very rare, although neither prevalence nor incidence are exactly known. The disease is found among all races and on all continents. For The Netherlands we estimated a frequency of at least one in 100 000 male births, and a prevalence of at least one in 200 000.16 Surveys in France17 and in the United States5 showed a similar frequency.