skip to main content

PD – Random On-Off Fluctuations — SCE Neurology MCQ

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

HardMovement DisordersPD – Random On-Off FluctuationsSCE Neurology

A 39-year-old has recurrent vomiting-triggered episodes of proximal weakness and encephalopathy. CK and acylcarnitines are normal between attacks. During relapse, muscle MRI shows oedema and biopsy reveals lipid storage; exome sequencing identifies biallelic ETFDH variants. Which treatment should be started promptly?

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

Reveal the answer and explanation

Correct answer: E — Oral riboflavin plus metabolic-dietetic management

Explanation lettering: C = shown as A · D = shown as B · E = shown as C · A = shown as D · B = shown as E

B is correct: late-onset multiple acyl-CoA dehydrogenase deficiency due to ETFDH can cause episodic or progressive lipid-storage myopathy, with screening acylcarnitines occasionally normal between crises, and often responds dramatically to riboflavin. A ketogenic high-fat regimen is inappropriate for impaired fatty-acid oxidation. Alglucosidase treats Pompe disease. Immunosuppression treats inflammatory myopathy, not a flavoprotein electron-transfer defect. Management also includes avoidance of fasting and specialist nutritional planning.

Reference: Proximal muscle weakness: https://pn.bmj.com/content/19/4/321