Adrenoleukodystrophy

From WikiGenetics

1 Name of Condition
2 Definition
3 Description, Signs and Symptoms
4 Inheritance
5 Demographics
6 Diagnosis
7 Treatment and Management
8 Prognosis
9 Resources
10 References

[edit] Name of Condition

Adrenoleukodystrophy, or ALD.

[edit] Definition

Adrenoleukodystrophy is a genetic, neurological disorder affecting the brain with demyelination. Demyelination is the stripping away of the fatty coating that keeps nerve pulses confined and maintains the integrity of nerve signals, thereby causing neurological deficits. Addison's Disease is also seen in 90% of ALD cases.

[edit] Description, Signs and Symptoms

The presentation of symptoms usually starts between ages 4-10, but there is a milder adult onset form of the condition.

Most common symptoms (behavioral):

abnormal withdrawal
aggression
poor memory
poor performance in school

Other symptoms:

visual loss
learning disabilities
seizures
poorly articulated speech
difficulty swallowing
deafness
disturbances of gait and coordination
fatigue
intermittent vomiting
increased skin pigmentation
progressive dementia

[edit] Inheritance

The most common is the X-linked form (X-ALD), which involves an abnormal gene located on the X-chromosome. Women have two X-chromosomes and are the carriers of the disease, but since men only have one X-chromosome and lack the protective effect of the extra X-chromosome, they are more severely affected.

[edit] Demographics

Affects 1 in every 17,900 boys worldwide.

[edit] Diagnosis

Brain MRI is always abnormal in ALD, and 85% of ALD sufferers' MRI shows a characteristic pattern of symmetrical enhanced T-2 signal in the parieto-occipital region with contrast enhancement at the advancing margin.

Laboratory analysis will show a high concentration of very long chain fatty acids (VLCFA) in plasma.

[edit] Treatment and Management

Symptomatic and supportive treatments for ALD include treatment with adrenal hormones, physical therapy, psychological support, and special education.

Recent evidence shows that "Lorenzo's Oil" (a mixture of oleic acid and erucic acid) can reduce or delay the appearance of ALD symptoms by normalizing VLCFA levels.

Bone marrow transplants can benefit boys with early evidence of ALD, but the procedure is too risky for those with more advanced cases.

Infants and young children with neonatal ALD may benefit from oral administration of docosahexanoic acid (DHA).

[edit] Prognosis

Prognosis for patients with ALD is generally poor due to progressive neurological deterioration. Death usually occurs within 1 to 10 years after the onset of symptoms.