Endocrine Abstracts

Case History: A 69-year-old woman with bipolar schizoaffective disorder of 11 year’s duration and recent diagnosis of atrial fibrilation was admitted with acute onset of delirium, lethargy, shakiness and confusion. On admission, the patient was restless and non-compliant. Her skin was warm and sweaty, clinically dehydrated. Her heart rate ranging between 75 and 100 /min. The rhythm was irregular, consistent with atrial fibrillation on ECG and was afebrile. She was oriented to time/place/person but trying to climb from bed. Her speech was dysarthric. She had coarse tremors generally and brisk tendon reflexes but no ataxia. Her recent medication were lithium 600 mg a day (started since 2009 with dose titration recently), valproate, clomipramine and procyclidine. At care home, the patient’s ability to perform self-care had worsened over the previous year. There was no family history of thyroid illness. Patient’s thyroid function was normal 2 months prior, checked by her psychiatrist/mental health team.

Investigation: FBC, U/Es, LFTs and Urine MSU results-normal, CRP: 28, CT head NAD, LP – NAD. Her TFTs on admission was consistent with hyperthyroidism with FT4: 62.2 pmol/l (7.86–14.41), TSH: <0.02 mU/l (0.35–5.5). Lithium level: 1.50 mmol/l (0.4–1.2), TRAB and TPO antibodies were normal.

Results/Treatment: Given history, symptoms and investigations patient was treated as Lithium induced hyperthyroidism and started on carbimazole 20 mg BD and lithium was stopped as per Psychiatry team. Next day patient became very agitated, developed temperature and became drowsy. She was not compliant with oral medications and hasn’t had her carbimazole doses. O/E: GCS: 10/15, HR:160 irregular, BP: 160/90, temp: 39. On Burch-Wartofsky Point Scale (BWPS) for Thyrotoxicosis, she was scoring 80 (highly suggestive of thyroid storm). Patient was treated as Thyroid storm secondary to Lithium and moved to ITU for the management. She was Started on PTU and beta-blocker via NG tube and IV hydrocortisone. Also given temperature she was covered with IV Antibiotics. Clinical and biochemical improvement noted 5–6 days post treatment. On day 9: FT4: 28.5 pmol/l, TSH: <0.02 mU/l. PTU was switched to oral carbimazole.

Conclusion and Point of Discussion: Hyperthyroidism is an uncommon side-effect of lithium compared to hypothyroidism but may have clinical implications. As this case suggested that early recognition of thyroid problem/Thyrotoxicosis in confused and agitated patient, especially if they are on offending agent like lithium is important and can be lifesaving.