RT Journal Article SR Electronic T1 Hashimoto encephalopathy in the 21st century JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP e217 OP e224 DO 10.1212/WNL.0000000000008785 VO 94 IS 2 A1 Mattozzi, Simone A1 Sabater, Lidia A1 Escudero, Domingo A1 Ariño, Helena A1 Armangue, Thais A1 Simabukuro, Mateus A1 Iizuka, Takahiro A1 Hara, Makoto A1 Saiz, Albert A1 Sotgiu, Stefano A1 Dalmau, Josep A1 Graus, Francesc YR 2020 UL http://n.neurology.org/content/94/2/e217.abstract AB Objective To report the presenting syndromes and to determine whether pretreatment criteria of Hashimoto encephalopathy (HE) predict response to steroids.Methods We assessed symptoms and steroid responsiveness in 24 patients with pretreatment criteria of HE, including (1) subacute onset of cognitive impairment, psychiatric symptoms, or seizures; (2) euthyroid status or mild hypothyroidism; (3) serum thyroid peroxidase antibodies (TPOAb) >200 IU/mL; (4) absent neuronal antibodies in serum/CSF; and (5) no other etiologies. Additional studies included determination of TPOAb (>200 IU/mL) in 74 patients with criteria of possible autoimmune encephalitis (AE) without neuronal antibodies and 205 patients with different neuroimmunologic diseases, psychosis, or new-onset refractory status epilepticus (NORSE). Serum antibodies to the amino (ΝΗ2)-terminal of α-enolase (NH2-α-enolaseAb) were examined in the indicated 24 patients and 13 controls.Results The 24 patients (14 women) with suspected HE had a median age of 48 years (range 8–79 years). Four syndromes were identified: psychiatric (7, 29%), encephalopathy (7, 29%), NORSE-like (6, 25%), and limbic encephalitis (4, 17%). Only 6 of 19 (31.6%) patients completely responded to steroids. The frequency of TPOAb in the 74 patients with possible AE (6 of 74, 8.1%) was similar to that of the 205 controls (17 of 205, 8.2%; p = 0.84). NH2-α-enolaseAb were identified in 1 of 24 suspected HE cases and 1 of 13 controls.Conclusion Current pretreatment criteria of HE do not predict steroid responsiveness. The detection of TPOAb across all control groups reveals their poor disease-specificity. NH2-α-enolaseAb did not help in the diagnosis of HE. These findings imply a redefinition of HE that requires a systematic exclusion of antibody-mediated encephalitis.AE=autoimmune encephalitis; HE=Hashimoto encephalopathy; IVIG=IV immunoglobulin; LE=limbic encephalitis; NORSE=new-onset refractory status epilepticus; TPOAb=thyroid peroxidase antibodies