Isaacs syndrome with LGI1 and CASPR2 antibodies after HPV vaccination: A case report

Abstract

Abstract Isaacs syndrome is peripheral nerve hyperexcitability characterized by spontaneous muscle twitching and rigidity and is often associated with antibodies to CASPR2 (contactin-associated protein-like 2) and LGI1(leucine-rich glioma-inactivated 1). We report a patient with Isaacs syndrome, including clinical features, electrophysiological and laboratory investigations and post-treatment response. The patient presented with limb pain, muscle twitching, numbness in the extremities and around the mouth, and hand rash after the second dose of HPV vaccine. Laboratory tests indicated positive for LGI1 antibodies, CASPR2 antibodies, anti- phosphatidylserine/prothrombin antibodies and anti-sulfatide antibodies. The patient's IVIG (intravenous immunoglobulin) treatment resulted in significant relief of symptoms and a negative antibody profile. This case report suggests a possible adverse reaction to HPV (Human Papilloma Virus) vaccination, which could be treated by attempting several periods of IVIG therapy. The underlying immune mechanisms need to be studied with further extensive data.