Thunderclap Headache: A Primary Symptom of a Steroid-Responsive Encephalopathy with Autoimmune Thyroiditis

Table 1

Diagnostic criteria for SREAT [6, 14].

1.	Encephalopathy characterized by cognitive impairment, neuropsychiatric symptoms, myoclonus, partial or generalized tonic-clonic epileptic seizures, and focal neurological deficits
2.	Euthyroid, subclinical, or mild-to-moderate clinical hypothyroidism (with corresponding TSH levels)
3.	Normal brain MRI or with nonspecific abnormalities
4.	Presence of antithyroperoxidase antibody and possibly antithyroglobulin antibody and/or anti-thyroid-stimulating hormone receptor stimulating antibody
5.	Absence of well-characterized neuronal antibodies in serum and CSF
6.	No evidence of infectious, toxic, neoplastic, or (other than thyroid-associated) metabolic disease
7.	Complete or near complete remission with steroid therapy