Endocrine Abstracts

Introduction: Hashimoto’s encephalopathy is a neurological disorder of unknown cause associated with thyroid autoimmunity. It is easy to misdiagnose or overlook and the symptoms frequently lead to mistaken neurological diagnoses. The disease may present in two types – a sudden vasculitic type or a progressive subacute type associated to cognitive dysfunction, confusion and memory loss.

Case report: A 34 year old male presented to our emergency department with impaired conscious level, tonic clonic convulsions with a 3-day history of loss of appetite,vomiting and altered mentation before admission. He is known to be thyrotoxic on carbimazole 30 mg/day, propranolol 40 mg however he was not compliant to treatment A week before admission he was diagnosed as bipolar disorder for which lithium carbonate 600 mg/day was prescribed. On physical examination: temperature 36.6°C, heart rate of 111/minute, blood pressure of 140/88 mm Hg, respiratory rate of 24/minute, and an oxygen saturation of 98% on room air. Glasgow coma scale 10 With no signs of lateralization. The laboratory findings: Hematologic and biochemical laboratory findings were normal, TSH:0.01, FT3:5.81, FT4:2.79, cerebrospinal fluid (CSF) normal, EEG demonstrated nonspecific slow waves without spikes, normal CT brain. The MRI revealed bilateral symmetrical cerebellar patchy areas. Lithium was stopped toxicity was suspected (level 1.3 mmol/l (0.4–2 mmol/l), anti microsomal antibodies >1300 IU/ml (n; <10.0 IU/ml), anti-TgAb titrers 382 IU/ml (n; <10.0 IU/mL),negative toxicology screen. Metabolic cause of coma was suspected. He was prescribed prednisolone (30 mg/d).subsequently increased to 50 mg/d with little improvement. Intravenous pulse methylprednisolone regimen (1 g/day) was introduced for three days together with 5 sessions of plasmapheresis. All cognitive dysfunction and neurologic symptoms resolved by 13 days. He was discharged on carbimazole 45 mg/day, prednisolone 60 mg/day tapered over 1 month.

Conclusion: Hashimoto encephalopathy is an extremely important, though rare, diagnosis. Hashimoto encephalopathy should be suspected and screened for in patients with encephalopathy due to unknown causes due to excellent response to treatment.