Adrenomyeloneuropathy

Adrenomyeloneuropathy is a form of X-linked adrenoleukodystrophy characterized by pronounced involvement of the spinal cord with only minor involvement of the cerebral white matter.

Clinical presentation

Clinical presentation depends on whether or not there is also cerebral involvement.

In the 'pure' form for adrenomyeloneuropathy, which has no direct cerebral involvement, the presentation is dominated by lower limb spastic paraparesis, sphincter dysfunction (mainly bladder) and sensory abnormalities such as sensory ataxia with vibration sense impairment . The upper limbs are generally spared .

When cerebral involvement is also present, typically occurring a decade or more after spinal involvement, then the presentation is typically with neuropsychiatric symptoms progressing to dementia .

The majority (70%) of patients eventually develop adrenocortical and testicular insufficiency .

An additional clinical feature is thin sparse head hair and early balding .

Radiographic features

MRI

In the pure form of adrenomyeloneuropathy, imaging is dominated by spinal cord atrophy primarily affecting the thoracic cord . Imaging of the brain is either normal or demonstrates minor abnormalities in the pyramidal tracts traversing the brainstem and internal capsules .

Cerebral involvement, if also present, appears similar to cerebral adrenoleukodystrophy and is discussed separately.