Walking Difficulties and Brainstem Dysfunction: a Case Report of Adult Onset Leigh Syndrome

Abstract

Leigh syndrome (LS) or subacute necrotizing encephalomyelopathy is a progressive, lethal, mitochondrial disease mostly presenting in childhood. We report a 36-year-old African male presenting to the Emergency Department with a 6-month history of progressive dysarthria. Examination also showed oculomotor limitations for downgaze and convergence, mild right hemiparesis with Babinski sign, and absent lower limb tendon reflexes. He revealed he was presenting mild walking difficulties since the age of 25. Family history was unremarkable. A brain magnetic resonance showed diffuse white matter lesions without enhancing around the third ventricle, in the medulla oblongata, and bilaterally to the caudate and the putamen. Polymerase-chain-reaction amplification of the mitochondrial genes, followed by direct sequencing, found a 10191T>C variant related to LS. To now, only 8 late-onset patients share the same pathogenic variant.