Endocrine Abstracts

Background: Persistent thyrotoxicosis despite medical therapy remains a major challenge and is widely attributed to suboptimal adherence. We present a case of thyrotoxicosis with severe adverse impact on health, who was successfully cured with thyroidectomy despite persistently raised thyroid hormones. We also propose that impact of thyrotoxicosis on mental health drives noncompliance setting up a vicious cycle.

Case: A 35-year-old woman with Graves’ disease (onset 2015, TSH <0.005mIU/l, T4 80.9pmol/l, T3>30,7pmol/l) remained thyrotoxic despite maximum dose of carbimazole and propylthiouracil. Adherence to medication (confirmed by prescription record), investigations and attendance was patchy with long gaps in follow up. By 2024, she had lost >20 kg weight and demonstrated features of apathetic thyrotoxicosis. Despite obvious challenges, radioiodine was discussed but declined by the patient. She agreed to thyroidectomy and was hospitalized for 2 weeks preoperatively for “supervised” Lugol’s iodine. Unfortunately, supervision of ingestion of medication proved difficult and after two weeks T4 was 24.3pmol/l and T3 17.9pmol/l. Surgery was high risk, but this was considered to be lower than from ongoing thyrotoxicosis. Invasive monitoring with arterial and femoral venous lines was instituted and remifentanil–esmolol infusions maintained cardiovascular stability. She was transferred to ICU for 24-hours and the remainder of her stay was uneventful. 2 months postoperatively she is euthyroid, compliant with thyroxine with remarkable improvement in physical and mental health

Conclusions: This case demonstrates that if clinical circumstances demand, thyroidectomy can be considered despite suboptimal biochemical control. Multidisciplinary care, pharmacological support and planned ICU care are required to mitigate the risk. We also hypothesize that bidirectional interaction between non-compliance and mental health effects is a major driver for persistent thyrotoxicosis. Altered serotonin and dopamine dynamics lead to low mood, impaired adherence, sustained thyrotoxicosis, and further worsening of mood. Supporting mental health is integral to successful management of severe hyperthyroidism.