Endocrine Abstracts

A 46-year-old male was brought to the hospital by his uncle as he was found to be acutely confused and agitated ‘talking rubbish’ and giggling inappropriately. Last time he was seen well was 3 days ago. He was a cyclist who lived alone and his past medical history included Graves’ disease and AF. He was on propranolol, carbimazole and warfarin. A month ago he needed admission to a different hospital after falling off his bike. At that time he also developed confusion and had undergone CT and MRI of his brain which were normal. An LP and EEG had excluded herpes encephalitis and the symptoms eventually had been attributed to opioid analgesics. On this admission, he was apyrexial, tachycardic, overtly confused and incoherent. He had prominent exopthalmos and fine tremor in both arms with brisk reflexes. The rest of the examination was unremarkable. There was mild leukocytosis and septic screen and CT head were normal. His TSH was 0.01 mU/l (0.27–4.2 mU/L) and fT4 was 43.2 pmol/l (11.0–25.0 pmol/L).This was felt not to be high enough to cause his psychotic presentation and it was queried whether his current symptoms could be related to psychiatric illness. The day after he was referred to the endocrine team because of the deranged TFTs and the advice given was to increase the carbimazole and check his anti TPO antibodies which came back >600 U/ml (<34.0 U/ml) The diagnosis of Hashimoto’s encephalopathy was made and the patient improved dramatically after having 20 mg of prednisolone OD. His TFTs a few weeks after were within range and as he was not a candidate for radioactive iodine, in view of his active ophthalmopathy, he had a partial thyroidectomy. He made a good recovery and currently is on thyroxine replacement and weaning dose of steroids.

TFTs are some of the basic tests we do when we are investigating confusion but this case illustrates that when a patient has already a background of thyroid disease it is advisable that we check specifically his antibody status. When other aetiologies have been excluded then remarkably raised anti TPO antibodies can provide the diagnosis of Hashimoto’s encephalopathy. It is a rare condition mostly associated with autoimmune thyroiditis and as it is highly responsive to steroids, an impressive reversal of the presenting symptoms can be expected.