Table 3.
Signs and symptoms encountered in mitochondrial disorders
| Disease | Mutation | Signs and symptoms |
|---|---|---|
| Kearns-Sayre syndrome | Large-scale mtDNA deletionĀ | Ataxia, peripheral neuropathy, muscle weakness, ophthalmoplegia, apoptosis, pigmentary retinopathy, sideroblastic anemia, diabetes mellitus, short stature, hypoparathyroidism, cardiomyopathy, conduction defects, |
| Myoclonic epilepsy with ragged-red fibers | mtDNA point mutation, tRNA abnormality | Seizures, ataxia, myoclonus, psychomotor regression, peripheral neuropathy, muscle weakness, short stature, sensorineural hearing loss, lactic acidosis, ragged-red fibers on muscle biopsy |
| Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes | mtDNA point mutation, tRNA abnormality | Seizures, ataxia, myoclonus, psychomotor regression, hemiparesis, cortical blindness, migraine, dystonia, peripheral neuropathy, muscle weakness, diabetes mellitus, short stature, cardiomyopathy, conduction defects, intestinal pseudoobstruction, sensorineural hearing loss, Fanconi syndrome, lactic acidosis, ragged-red fibers on muscle biopsy |
| Progressive external ophthalmoplegia | Large-scale mtDNA mutation | Muscle weakness, ophthalmoplegia, apoptosis, lactic acidosis, ragged-red fibers on muscle biopsy |
| Pearson’s syndrome | Large-scale mtDNA mutation | Anemia, pancreatic dysfunction, Fanconi syndrome, lactic acidosis, ragged-red fibers on muscle biopsy |
| Neuropathy, ataxia, and retinitis pigmentosa | mtDNA point mutations, mRNA abnormality | Ataxia, peripheral neuropathy, muscle weakness, pigmentary retinopathy, optic atrophy, sensorineural hearing loss |
| Maternally inherited Leigh’s syndrome | mtDNA point mutations, mRNA abnormality | Seizures, ataxia, psychomotor regression, dystonia, muscle weakness, pigmentary retinopathy, optic atrophy, cardiomyopathy, lactic acidosis |
| Leber’s hereditary optic neuropathy | Multiple mtDNA point mutations, mRNA abnormality | Dystonia, optic atrophy, cardiac conduction defects |
mRNA: Messenger RNA; mtDNA: mitochondrial DNA; tRNA: transfer RNA. Information in Table 3 is modified from the study of Muravchick (2008).