Palatal-Myoclonus as a Presentation of Hashimoto Encephalopathy: an interesting case report
A previously healthy 32 years old; veterinarian male, referred to the emergency department complaining about 2 episodes of generalized tonic clonic seizure within the past 24 hours.\nAccording to his wife, he had depressed mood and psychomotor slowing during the past 3 weeks. He also had episodes of confusion, agitation, visual hallucinations, decrement of interpersonal relationship, generalized purities and flushing.\nThree days before admission, he had abnormal movements of the palate and tongue.\nOn physical examination, the patient was ill and lethargic. There was a low grade fever (Temp: 37.4 Auxiliary), but other vital signs were normal. His neck was supple. On general examination, there were itching excoriations on his skin, but other systemic examinations were normal. Neurologic examination was normal, apart from mild confusion and myorrhythmic movements of tongue and soft palate. The patients MRI showed abnormal symmetric hyper signality in both caudate nuclei and putamens on T2 and FLAIR. () There was no abnormal signal in medulla (inf.olive nucleus). ()\nThe CSF was clear with normal level of protein and glucose. There were 30 red blood cells, 20 lymphocytes and no polymorphonuclear in CSF. PCR for herpes simplex virus and mycoplasma were negative. The EEG showed intermittent delta and theta activity. Routine blood counts, renal function tests and glucose were within normal limits. Erythrocyte sedimentation rate (ESR) and C-reactive protein were normal. Liver function tests were elevated. Antinuclear antibodies, anti-ds-DNA, anti SS-A, anti SS-B, lupus anticoagulant, anti phospholipid Ab and RF were normal. The human immunodeficiency virus antibody was negative. Chest radiograph and ultrasonographic scan of the abdomen did not reveal any tumor. Thyroid function tests were within normal limits, but the thyroid thyroglobulin antibody (TGHA) titer was 120 IU/mL (normal < 22 IU/ml) and the thyroid peroxidase antibody (Anti-TPO) titer was 356U/mL (normal < 60 IU/ml).\nA diagnosis of HE was made, and the patient was treated with oral prednisolone 1 mg/kg/d, levothyroxin and anticonvulsants. Before starting treatment with prednisolone, the patient had 3-4 episodes of simple focal seizures per day which were not controlled with antiepileptic drugs. Less than 24 hours after the initiation of prednisolone, the palatal myorrhythmic movements, itching, and flushing were subsided and focal seizures never repeated. We did not do needle biopsy of thyroid gland. On the follow-up, at days 10 and 40, the patient had no seizures and the palatal myorrhythmic movements disappeared; and EEG was normal at 40th. The Anti- TPO level was decreased to 73 IU/ml after 6 months.