Contactin associated protein-like 2 (CASPR2) and leucine-rich glioma-inactivated protein 1 (LGI1) voltage gated potassium channel (VGKC) proteins are found in both the central and peripheral nervous systems [1]. Antibodies against these proteins are associated with encephalopathy, seizures, peripheral nerve hyper-excitability, autonomic dysfunction, hyponatremia, pain, and insomnia in varying severity and combination [1].
Morvan syndrome, first described in 1890, combines symptoms of peripheral nervous system (PNS), central nervous system (CNS), and autonomic nervous system dysfunction. It was later found to be associated with VGKC-complex antibodies, mainly against CASPR2 or LGI1 or both.
Our patient had a history of anti-LGI1 positive limbic encephalitis, which presented years later with anti-CASPR2 positive Morvan syndrome.