A 46-year-old woman presents with weight loss. On examination, you note that she has prominent eyes, ‘lumpy’ swelling over her shins and the neck lump seen in the image above.

1. What is the most likely diagnosis?

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This patient has a history of weight loss in combination with prominent eyes, swelling over her shins and a goitre. The most likely underlying diagnosis is that of Grave’s disease, with the prominent eyes representing Grave’s ophthalmopathy.

Grave’s disease is an autoimmune disease caused by the abnormal production of a TSH receptor antibody that causes the excessive production of thyroid hormones.

Question image adapted from Wikipedia
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2. What is the rash on her shins likely to be?

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The lumpy rash on her shins is likely to be pretibial myxoedema.

3. Which blood test can confirm this SPECIFIC diagnosis?

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A low TSH and an elevated T3 or T4 would occur in hyperthyroidism of any cause, and this is not diagnostic of Grave’s disease.

The thyroid-stimulating immunoglobulin (TSI) assay is almost always positive in Grave’s disease and, when positive, is diagnostic for it.