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Start free with EleplanMFF-related encephalopathy due to mitochondrial and peroxisomal fission defect
ORPHA:485421Etiological subtype
Also called Leigh-like basal ganglia disease-optic atrophy-peripheral neuropathy syndrome · Leigh-like encephalopathy-optic atrophy-peripheral neuropathy syndrome
What it is
Orphanet has not published a description for this disease yet. The identifiers, classification and cross-references below are still current.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy
- Inheritance
- Autosomal recessive
- Classified as
- Etiological subtype
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Common30–79%
27- Abnormal basal ganglia MRI signal intensity
- Abnormality of visual evoked potentials
- Abnormal mitochondrial shape
- Abnormal thalamic MRI signal intensity
- Axial hypotonia
- Cerebellar atrophy
- Decreased nerve conduction velocity
- Developmental regression
- Dysphagia
- EEG abnormality
- External ophthalmoplegia
- Feeding difficulties
- Functional motor deficit
- Hyperreflexia
- Hypsarrhythmia
- Impaired use of nonverbal behaviors
- Motor delay
- Muscle weakness
- Nasogastric tube feeding
- Optic atrophy
- Optic disc pallor
- Profound global developmental delay
- Secondary microcephaly
- Seizure
- Sound sensitivity
- Spasticity
- Visual impairment
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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