skip to main content

Mitochondrial MELAS — SCE Neurology MCQ

Instant feedback + full explanation. One question, done properly.

HardNeurogenetics and NeuroimmunologyMitochondrial MELASSCE Neurology

A 63-year-old woman presented with stroke-like episodes, seizures and sensorineural deafness in a young adult. On examination, there was short stature and lactic acidosis. Initial investigations showed: MRI lesions crossed vascular territories; mtDNA m.3243A>G was detected. Where is the most likely anatomical localisation?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Cerebral cortex affected by mitochondrial energy failure across vascular territories

The best answer is “Cerebral cortex affected by mitochondrial energy failure across vascular territories”. UK stroke guidance supports urgent vascular imaging and reperfusion selection, short-course dual antiplatelet therapy for eligible minor stroke or high-risk TIA, decompression for life-threatening swelling, and secondary prevention matched to mechanism. The alternatives “Internal capsule supplied by lenticulostriate perforating arteries, after specialist assessment”, “Dorsal columns affected by length-dependent axonal degeneration, when the phenotype supports it”, “Basal ganglia affected by isolated dopamine depletion, within the relevant UK pathway”, “Cerebellar peduncles affected by focal inflammatory demyelination, after excluding important mimics” are clinically adjacent possibilities, but they do not match the defining chronology, localisation, physiology, investigation result or UK management sequence in this stem.

Reference: National Clinical Guideline for Stroke: acute care: https://www.strokeguideline.org/chapter/acute-care/