A 58-year-old man presents with 6 months of progressive insomnia, vivid hallucinations, confusion, and profuse sweating. Examination reveals continuous spontaneous muscle twitching that persists even during attempted sleep, along with tachycardia and hypertension. EMG shows high-frequency motor unit discharges (150–300 Hz). Overnight EEG shows the pattern marked **B** in the diagram — loss of normal sleep architecture with continuous mixed wake-like and drowsy rhythm without clear NREM or REM stages. Anti-CASPR2 IgG antibodies are detected. Which of the following is the most likely diagnosis?
Ready to test yourself?
Test your Medicine knowledge with AI-powered MCQs and detailed explanations — no signup required to try.
Sign up free and practice all 1 Morvan Syndrome (Anti-CASPR2) MCQs with AI-powered explanations tailored to your performance.
Create Free Account