Thyrotoxicosis factitia complicating Graves' disease

Area of Science:

• Endocrinology
• Nuclear Medicine
• Pharmacology

Background:

• Graves' disease is an autoimmune disorder causing hyperthyroidism.
• Radioactive iodine ((131)I) therapy is a common treatment for hyperthyroidism.
• Factitious thyrotoxicosis can complicate treatment management.

Purpose of the Study:

• To investigate the cause of persistent hyperthyroidism in a patient after (131)I therapy.
• To identify the source of excessive thyroid hormone levels despite prescribed treatment.
• To highlight the importance of medication adherence and monitoring in Graves' disease management.

Main Methods:

• Clinical assessment of hyperthyroid symptoms and biochemical markers.
• Monitoring of thyroidal uptake of radioactive iodine ((131)I).
• Review of patient's medication history, including prescription tracing.
• Supervised withdrawal of antithyroid drugs and thyroxine.

Main Results:

• Patient remained hyperthyroid post-intravenous (131)I therapy, despite normal thyroidal uptake.
• Prescription tracing revealed the patient obtained significantly excess amounts of thyroxine.
• Supervised cessation of all medications led to rapid normalization of thyroid status (euthyroid state).

Conclusions:

• Factitious administration of excess thyroxine was the cause of persistent hyperthyroidism.
• Careful medication history and prescription verification are crucial in managing complex endocrine cases.
• This case underscores the challenges in diagnosing and treating patients with Graves' disease who self-medicate.