Endocrine Abstracts

Clinical presentation: This 32 year old lady was referred with a history of weight loss, sweating, tremor and anxiety and biochemical hyperthyroidism; fT4 41 pmols/l (9.00–25.00 pmols/l) TSH <0.05 miu/l (0.30–5.00 miu/l); strongly positive TPO antibodies (1600 IU/ml.). She was toxic clinically, had subtle left sided proptosis and a palpable left sided thyroid nodule. She was started on carbimazole 20 mg and the initial differential diagnosis was between Grave’s disease and a toxic thyroid nodule.

Further investigation: A technetium uptake scan surprisingly showed a cold nodule correlating clinically with the palpable nodule. Fine needle aspiration (FNA) was initially non-diagnostic but repeat FNA demonstrated papillary thyroid cancer. By the time of the FNA, her hyperthyroidism had gone into remission. On discussion with the patient, it was decided she would undergo a total thyroidectomy rather than hemi-thyroidectomy, both to definitely treat her auto-immune hyperthyroidism as well as remove the malignant nodule.

Learning points: This young lady presented with auto-immune hyperthyroidism and a malignant thyroid lesion. The lesson here is that that all thyroid nodule nodules require investigation even in the context of hyperthyroidism, as dual pathology may exist. The other interesting aspect of this case was to recommend a total thyroidectomy both to remove the lesion and definitively cure her hyperthyroidism, thereby killing two birds with one stone.