Vitamin B1 & B12 levels normal, tumor markers normal, ESR normal, CRP normal, immunoglobulins normal, complements normal, RF negative, antiphospholipid antibodies negative, GFAP IgG negative, Autoimmune encephalitis antibodies negative, paraneoplastic antibodies negative, serum cytokines (IFN-γ, IL-6, IL-4, IL-2, IL-10, IL-21, TNF-ɑ) normal, ANA, positive SSA positive, SSB positive, Ro-52 positive, and p-ANCA positive. Here, IL21 is linked to autoimmune encephalitis.