ISCA2

Clinical Characteristics

The clinical features of this disease may include followings with imaging and supportive laboratory findings:

Neurologic findings

  • Progressive loss of developmental milestones, typically beginning between ages three and seven months
  • Spasticity
  • Impaired speech

Ophthalmologic features

  • Optic atrophy
  • Loss of eye contact
  • Nystagmus
  • Visual impairment

Brain MRI findings

  • Diffuse bilateral symmetric signal abnormality in cerebral white matter
  • In some cases, signal abnormalities in the corpus callosum, internal capsule, midbrain, middle cerebellar peduncles, and cervical spinal cord

Supportive laboratory findings

  • Biochemical Analysis
  • Increased CSF glycine, glutamate, and lactate
  • Fibroblasts show decreased mitochondrial complex I and II activity
  • Mildly decreased complex IV activity
  • Decreased mtDNA levels
  • Decreased mitochondrial membrane potential
  • Decreased oxidative phosphorylation and ATP production
  • Respiratory chain enzyme analysis on muscle tissue reveals deficient activity of complex II and IV