<unk>  can present in different ways. The different presentations are complicated by the pattern of X-linked recessive inheritance. There have been seven phenotypes described in males with ABCD1 mutations and five in females. Initial symptoms in boys affected with the childhood cerebral form of<unk>  include emotional instability, hyperactivity and disruptive behavior at school. Older patients affected with the cerebral form will present with similar symptoms. Untreated, cerebral<unk>  is characterized by progressive demyelination leading to a vegetative state and death. Adult males with an adrenomyeloneuropathy presentation typically present initially with muscle stiffness, paraparesis and sexual dysfunction. All patients with clinically recognized<unk>  phenotypes are at risk for adrenal insufficiency. There is no reliable way to predict which form of the disease an affected individual will develop, with multiple phenotypes being demonstrated within families. Onset of adrenal insufficiency is often the first symptom, appearing as early as two years of age. Male<unk>  phenotypes + Male<unk>  phenotypes Phenotype Description Onset Approximate relative frequency Childhood cerebral Progressive neurodegenerative decline, leading to a vegetative state without treatment 3–10 years 31–35% Adolescent Similar to childhood cerebral, with a slower progression 11–21 years 4–7% Adrenomyeloneuropathy (AMN) Progressive neuropathy, paraparesis; approximately 40% progress to cerebral involvement 21–37 years 40–46% Adult cerebral Dementia, behavioral disturbances, similar progression to childhood cerebral form, but without preceding AMN phenotype Adulthood 2–5% Olivo-ponto-cerebellar Cerebral and brain stem involvement Adolescence to adulthood 1–2% "Addison disease only" Adrenal insufficiency Before 7.5 years Up to 50% in childhood, varies with age Asymptomatic No clinical presentation, further studies can reveal subclinical adrenal insufficiency or mild AMN phenotype Most common phenotype in boys under four years of age Proportion of asymptomatic patients decreases with age Female<unk>  phenotypes + Female<unk>  phenotypes Phenotype Description Onset Approximate relative frequency Asymptomatic No neurologic or adrenal involvement Most women under 30 do not have any neurologic involvement Diminishes with age Mild myelopathy Increased deep tendon reflexes, sensory changes in lower extremities Adulthood Approximately 50% of women over 40 years of age Moderate to severe myeloneuropathy Similar to male AMN phenotype, but later onset and milder presentation Adulthood Approximately 15% of women over 40 years of age Cerebral involvement Progressive dementia and decline Rare in childhood, more common in adults ~2% Adrenal involvement Primary adrenal insufficiency Any age ~1%
Adrenoleukodystrophy
Hereditary inclusion body myopathy
Inclusion body myositis
Mitochondrial myopathy
Familial amyloid neuropathy
Familial amyloid polyneuropathy
Charcot–Marie–Tooth disease
Lambert–Eaton myasthenic syndrome