Presentation
Severe thyrotoxicosis and large goitre.
Patient Data

Diffuse enlargement of the thyroid gland, with evidence of a pyramidal lobe. Mild narrowing of the trachea.

Diffuse increased tracer uptake within both lobes of an enlarged thyroid gland.
The TSH Receptor Ab (TRAB) is highly positive, consistent with Graves disease.
Case Discussion
Graves disease is an autoimmune disease characterised by hyperthyroidism triggered by thyroid-stimulating antibodies. Another differential diagnosis for an enlarged thyroid and circulating antibodies includes Hashimoto's thyroiditis. However, the presence of TSH receptor antibody (TRAb) is most consistent with Graves disease.