Endocrine Abstracts

A 54 year old male was referred by GP for abnormal TFT. Thyroid function was done routinely. TSH 3.0 (normal 0.5 to 4.5), FT4-25.2. GP repeated the TFT twice, and both of them were similar. There were no clinical features of Thyrotoxicosis. On examination, his heart rate was 78/min regular, wt 79 kg, no thyroid enlargement, no tremor. Cardiovascular examination was unremarkable. He is fit and well gentleman. He does not take any regular medication. No history of taking any other over the counter medications also. He is a smoker for 30 years. No family history of thyrotoxicosis. After 3 months his TFT was repeated and it showed TSH-1.6 and FT4-27.7. Anti TSH receptor Ab was negative. Repeat TFT after 6 months was also similar. In both occasions patient was asymptomatic with high FT4.

Questions:: 1) What is the probable diagnosis?

2) How should we manage this case with Asymptomatic isolated Thyroxinaemia?