Endocrine Abstracts

Background: Recombinant human TSH (rhTSH) promotes ¹³¹I uptake in selected populations. Lithium increases RAI retention by reducing intra-thyroidal release. In this report, combination of rhTSH and lithium overcame low RAIU in Graves’ disease.

Objective: We aim to present the case of a Graves’ disease given combination of rhTSH and lithium to overcome amiodarone-induced low ¹³¹I uptake.

Methods and results: A 39-year old female with Graves’ disease acquired thionamide-induced agranulocytosis and went into cardiorespiratory arrest. She had ventricular tachyarrhythmias on resuscitation and cardioverted with amiodarone. She was subsequently placed on hydrocortisone (150 mg/day), amiodarone (200 mg/day) and propranolol (60 mg/day). She was referred to our institution for definitive Graves’ disease management. On admission, she was normotensive, tachycardic, and afebrile, with fine tremors, hyperreflexia, and diffuse thyromegaly. She had normal complete blood count, hypokalemia, elevated ALT and low TSH (0.03 μIU/l, NV 0.27–3.75). Thyroid ultrasound showed diffuse thyromegaly with uniform echopattern and normal color flow doppler. RAIU was low at 4 and 24 h (6 and 7%, respectively). In preparation for RAI therapy, she was given lithium 900 mg/day and two doses of 0.9 mg i.m. rhTSH. Repeat RAIU after the 2nd dose of rhTSH showed a more than 5-fold increase in 4 h uptake (32 vs baseline 6%). She was given 131-I 25 mCi after the 2nd dose of rhSTH. Clinical and biochemical course continuously improved thereafter.

Conclusion: This is the first case to demonstrate the efficacy of combining rhTSH and lithium to overcome amiodarone-induced low 131-Iodine uptake in Graves’ disease.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.