CNTNAP2 and Isaacs syndrome: We report a case of Isaacs with positive CASPR2, LGI1, anti-phospholipid antibody, and anti-Sulfatide antibody after the second dose of qHPV vaccine, and described the classic clinical feature of Isaacs: muscle spasms, which was confirmed by Cerami and Maryam Hatami.[10,11] In fact, Isaacs syndrome is an autoimmune disease characterized by neurogenic myotonia.