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Start free with EleplanCongenital lactic acidosis, Saguenay-Lac-Saint-Jean type
ORPHA:70472Disease
Also called COX deficiency, French-Canadian type · Cytochrome C oxidase deficiency, French-Canadian type · Cytochrome oxidase deficiency, Saguenay-Lac-Saint-Jean type · Leigh syndrome, French-Canadian type · Leigh syndrome, Saguenay-Lac-Saint-Jean type · SLSJ-COX deficiency
What it is
A rare degenerative mitochondrial disease characterized by chronic metabolic acidosis, hypotonia, facial dysmorphism and delayed development.
Key facts
- Age of onset
- Infancy, Neonatal
- Inheritance
- Autosomal recessive
- Classified as
- Disease
Signs and symptoms
Very common80–99%
10Common30–79%
18- Abnormality of movement
- Ataxia
- Chorea
- Cytochrome C oxidase-negative muscle fibers
- Decreased liver function
- Developmental regression
- EEG with abnormally slow frequencies
- Focal T2 hyperintense basal ganglia lesion
- Hepatic steatosis
- Hypertrophic cardiomyopathy
- Inability to walk
- Multifocal epileptiform discharges
- Muscle weakness
- Peripheral neuropathy
- Poor speech
- Progressive neurologic deterioration
- Seizure
- Spasticity
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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