Hormone Responsive Hashimoto Encephalopathy: A Case of Hashimoto Encephalopathy Treated with only Oral Thyroid Medication and Symptomatic Therapy for Seizures and Psychosis, but without Steroids

Abstract

Hashimoto encephalopathy is a rare disease associated with autoimmune thyroiditis. Symptoms may include delirium, encephalopathy, seizures, and psychosis. Pathophysiology of this disease is not completely understood. This condition is often under-diagnosed if not suspected and should be considered in patients with diverse neuropsychiatric manifestations in whom no obvious etiology of encephalopathy can be determined. Anti-thyroid antibodies and thyroid peroxidase antibodies are crucial for diagnosis. Along with supportive management, empiric steroid treatment is usually administered as soon as infectious and other causes are ruled out. We report a case of Hashimoto thyroiditis which presented with agitation, psychosis, hallucinations, complex partial seizures. In this case the disease was controlled with only oral thyroid therapy and supportive management with antiepileptic drugs and antipsychotic drugs, but without the use of steroids.Keywords: Hashimoto encephalopathy; Autoimmune thyroiditis; Seizures; Delirium IntroductionHashimoto encephalopathy was first described in 1966 by Brain et al. [1] in a 49-year-old man with progressive impairment of consciousness and cognition interspersed with episodes of confusion or coma, agitation, hallucinations, tremor and recurrent stroke-like episodes, who had histologically confirmed Hashimoto thyroiditis [1]. Several cases of Hashimoto encephalopathy have been reported since then [2][3][4][5]. There are however controversies regarding its establishment as a specific disorder. Case HistoryA retired 71-year-old man living independently presented to the emergency department with new onset complex partial seizures and psychotic behavior. Laboratory work up revealed normal complete blood count, serum electrolytes, kidney function and liver function, however his thyroid stimulating hormone level was high with low free thyroxine levels. Magnetic resonance imaging of brain was normal. A preliminary diagnosis of secondary seizure was made and the patient was treated with antiepileptic drugs and was discharged home on oral thyroid supplement with plans to obtain an outpatient electroencephalogram and neurology follow up in clinic. The seizures recurred and his psychosis worsened over next two days evolving to partial complex status epilepticus and encephalopathy with delirium. He presented again to the emergency department and was admitted for further workup and management. Electroencephalogram was severely abnormal with diffuse polymorphic slowing and sharp wave activity suggesting epileptic encephalopathy. His clinical course at that time was associated with delirium and acute psychosis manifested as visual hallucinations, agitation, manic episodes and insomnia.Laboratory work up revealed normal complete blood count, serum electrolytes, kidney function and liver function, his thyroid stimulating hormone was elevated to 77.4 and free thyroxine levels was very low, 0.8. Cerebrospinal fluid analysis was normal, no evidence of infection was found in blood, urine and cerebros...