Multiple mitochondrial dysfunctions syndrome type 4

What is Multiple mitochondrial dysfunctions syndrome type 4?

A rare, severe, genetic, neurometabolic disease characterized by infantile-onset of progressive neurodevelopmental regression, optic atrophy with nystagmus and diffuse white matter disease. Affected individuals usually have central hypotonia that progresses to limb spasticity and hyperreflexia, eventually resulting in a vegetative state. Recurrent chest infections are frequently associated and seizures (usually generalized tonic-clonic) may occasionally be observed. Brain magnetic resonance imaging shows diffuse bilateral symmetric abnormalities in the cerebral periventricular white matter, with variable lesions in other areas but sparing the basal ganglia.

Other condition names

  • MMDS4

Inheritance type

Autosomal recessive


  • Worldwide: <1 in 1,000 000

Age of Onset

  • Infancy
Orphadata: Free access data from Orphanet. © INSERM 1999. Available on "". Data version 1.3.16 / 4.1.7.