Abstracts

Rationale: SREAT is a rare clinical entity associated with acute to subacute onset of altered mental status, seizures, and tremors in the setting of elevated thyroid peroxidase antibodies (TPO) and anti-thyroglobulin antibodies (TgAb). Although rare, detailed investigations and early treatment are paramount in preventing morbid neurologic sequelae. Herein, we report a case of Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), where early diagnosis and treatment resulted in complete recovery. Methods: Case: A19-year-old female with past medical history of hypothyroidism presented with multiple episodes of new-onset generalized tonic-clonic convulsions.  Neurological exam was remarkable for altered mental sensorium. Investigations revealed a high TSH (17.4), high TPO (113.3) and a high TgAb (7.7). A lumbar puncture revealed lymphocytic pleocytosis with mildly elevated protein. MRI showed nonspecific T2 hyperintensities in bilateral frontal lobes.  Continuous EEG monitoring showed ongoing generalized seizures, which were controlled with lacosamide, phenytoin, and levetiracetam. Other possible diagnoses were excluded by appropriate testing such as serology, CSF studies, cerebral angiogram and urine toxicology.  A presumptive diagnosis of Steroid-Responsive Encephalopathy associated with Thyroiditis was made, and the patient was started on high dose intravenous methylprednisolone (1000 mg for five days). Her mentation began improving significantly over the course of 5 days and returned to normal. Due to improvement with steroids, a diagnosis of SREAT was made, and the patient was discharged on an oral prednisone taper with a follow-up.  Results: Our case demonstrates that a comprehensive investigation to rule out other etiologies and early treatment with steroids entails a good outcome. Conclusions: SREAT is a rare but treatable cause of encephalopathy. Only 121 cases of SREAT have been reported in a systematic review published in 2006. Although a diagnosis of exclusion, it should be suspected more often in patients with acute to subacute onset of encephalopathy associated with seizures and tremors. Funding: None