Effectiveness of immunotherapy in a CASPR2 and LGI1 antibody-positive elderly patient with Isaacs’ syndrome: a case study

Excerpt

Isaacs’ syndrome (IS) is an acquired autoimmune disorder which causes peripheral nerve hyperexcitability, characterized by spontaneous muscle twitching, stiffness, and cramping of muscle extremities. It is regarded as a voltage-gated potassium channel (VGKC) antibody-mediated autoimmune disease [1]. VGKC is mainly responsible for regulating current across nerve cell membranes, which consequently influences the generation of neuronal action potentials [2]. VGKC comprises of various protein components, among which antibodies against contactin-associated protein-like 2 (CASPR2) and leucine-rich glioma-inactivated 1 (LGI1) are associated with IS [1]. While anti-epileptics usually relieves symptoms in IS patients, it is ineffective or only partially effective in VGKC antibody-positive IS patients. Immune therapy has been shown to be an effective treatment strategy in CASPR2 antibody-positive IS. Here, we describe the effectiveness of immune therapy in a CASPRS2 and LGI1 antibody-positive IS patient. …