voltage-gated calcium channel, voltage-gated potassium channel, or other currently recognized paraneoplastic antibodies) to support another diagnosis
In imaging studies no evidence for vascular, neoplastic or structural lesions that might explain the symptoms
Complete or nearly complete remission after initiation of glucocorticoid therapy. Definition
A relapsing encephalopathy occurs in association with autoimmune (Hashimotos or Ords thyroiditis), with high titers of antithyroid antibodies. Clinically, the condition may present one or more symptoms. Onset is often gradual and may go unnoticed by the patient and close associates to the patients. Symptoms sometimes resolve themselves within days to weeks, leaving a patient undiagnosed. For many other patients, the condition may result in ongoing problems with a variety of manifestations, often confusing clinicians due to the diffuse nature of symptoms. Differential diagnosis
Alzheimers disease
Cerebrovascular accidents (stroke)
Creutzfeldt–Jakob disease
Epilepsy
Migraine (including basilar, hemiplegic, and retinal types)
Other forms of autoimmune encephalitis, including forms of limbic encephalitis such as anti-NMDA receptor encephalitis
Schizophrenia
Spontaneous cerebrospinal fluid leak
Viral encephalitis
Transient ischemic attack

Treatment
Because most patients respond to corticosteroids or immunosuppressant treatment, this condition is now also referred to as steroid-responsive encephalopathy.Initial treatment is usually with oral prednisone (50–150 mg/day) or high-dose intravenous methylprednisolone (1 g/day) for 3–7 days. Thyroid hormone treatment is also included if required.Failure of some patients to respond to this first-line treatment has produced a variety of alternative treatments, including azathioprine, cyclophosphamide, chloroquine, methotrexate, periodic intravenous immunoglobulin, and plasma exchange. No controlled trials have been conducted, so the optimal treatment is not known.Seizures, if present, are controlled with typical antiepileptic agents. Prognosis
Duration of treatment is usually between 2 and 25 years.
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