TPO and neoplasm: Besides, most limbic encephalitis were para-neoplastic disease, since our patients have negative tumor antigens and neuronal nuclear antibodies screening (including anti-Hu IgG, anti-Yo IgG, anti-Ri IgG, anti-CV2 IgG et al), and negative serum VGKC antibody as well as the elevated titers of antithyroid antibodies (anti-TPO levels were greater than 1,300 IU/ml in five HE patients; the other three patients had anti-TPO levels greater than 400 IU/ml,Anti-TG levels were greater than 90 IU/ml in all eight cases), thus we might not first consider the diagnosis of the limbic encephalitis.