Symptoms: Psychomotor regression (loss of acquired skills), abnormal respiration, vomiting, seizures, hypotonia, nystagmus (oscillation of the eyeballs), poor reflexes, eating and swallowing difficulties, ataxia, dystonia (abnormal posturing of the limbs). Leigh syndrome is a neurodegenerative disorder with onset usually in infancy or childhood, rarely in teens and adults. It is characterized on MRI by necrotizing (dead or dying tissue) lesions on the brain, particularly in the basal ganglia and brainstem. There is more than one genetic defect that causes Leigh's Disease. According to Dr. David Thorburn, at least 26 defects have been identified. These include pyruvate dehydrogenase (PDHC) deficiency, and respiratory chain enzyme defects (complexes I, II, IV, and V). Depending on the defect, the mode of inheritance may be X-linked (defect on the X chromosome) usually affecting males only), autosomal recessive (one mutation from the mother and one from the father), and maternal (mtDNA mutation from mother only). There may also be spontaneous cases that are not inherited at all.
There is no cure for Leigh syndrome. Treatments generally involve cocktails of vitamins and supplements, which are only partially effective.
Supplements include: thiamine, CoQ10, riboflavin, biotin, creatine, and idebenone. Experimental drugs such as dichloroacetate (DCA) are also being tried in some clinics.
The prognosis for Leigh syndrome is poor. Depending on the defect, individuals typically live a few years.