Neurological abnormalities
• Early-onset progressive psychomotor regression
• Seizures
• Dystonia
Microvasculature abnormalities
• Petechiae and/or purpura
• Orthostatic acrocyanosis
• Hemorrhagic suffusions of mucosal surfaces
• Chronic hemorrhagic diarrhea
MRI abnormalities
• Symmetric patchy T2-weighted signals in the basal ganglia, periventricular white matter and dentate nuclei, brain stem, and cerebellar white matter. In some instances, cortical atrophy and diffuse leukoencephalopathy are present.
• Atypical neuroradiologic patterns were also reported
Laboratory abnormalities
• Increased blood lactate levels
• Increased blood C4-acylcarnitine esters
• Increased blood C5-acylcarnitine esters
• Increased plasma thiosulphate
• Increased urinary ethylmalonic acid
Mitochondrial biochemistry abnormalities
• Reduced cytochrome c oxidase (COX, complex IV) in brain, muscle and colon