Morvan syndrome is a rare autoimmune neurologic syndrome..
Target: Kv1 voltage-gated potassium channel (VGKC) complex
Autoantibodies include:
(1) CASPR2 = contactin associated protein 2
(2) LGl1 = leukcine-rich glioma inactivated 1
It may occur as a paraneoplastic syndrome in a patient with thymoma.
Clinical features:
(1) acquired neuomyotonia (peripheral nerve hyperexcitability that causes spontaneous muscular activity)
(2) mood changes
(3) hallucinations
(4) insomnia
(5) confusion or disorientation
(6) autonomic dysfunction
(7) in patients with anti-LGl1 there can be cardiac abnormalities (bradycardia, arrhythmia, AMI-like ECG changes)
(8) variable ataxia
(9) variable hyponatremia
