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Start free with EleplanCombined oxidative phosphorylation defect type 27
ORPHA:477774Disease
Also called COXPD27
What it is
A rare mitochondrial oxidative phosphorylation disorder characterized by a variable clinical phenotype including infantile onset of epileptic encephalopathy, hypotonia, global developmental delay, failure to thrive, complex movement disorder, and liver involvement, as well as childhood onset of severe myoclonus epilepsy, cognitive decline, progressive hearing and visual impairment, and progressive tetraparesis. Serum lactate may be increased, and brain imaging shows variable atrophy and white matter abnormalities.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Childhood, Infancy
- Inheritance
- Autosomal recessive
- Classified as
- Disease
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%
17- Abnormal cerebral white matter morphology
- Decreased activity of mitochondrial complex I
- Decreased activity of mitochondrial complex III
- Decreased activity of mitochondrial complex IV
- Developmental regression
- Diffuse cerebral atrophy
- Epileptic encephalopathy
- Generalized myoclonic seizure
- Global developmental delay
- Hearing impairment
- Increased circulating lactate concentration
- Intellectual disability
- Multifocal seizures
- Progressive visual loss
- Ragged-red muscle fibers
- Status epilepticus
- Tetraparesis
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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