How is Graves' Disease diagnosed?

There are a number of investigations used in the diagnosis of Graves' disease:

1. Free T3 and T4 Levels
In classical cases, both T3 and T4 are elevated

2. Serum TSH Levels
Serum TSH levels are classically suppressed.

3. Radioactive Iodine or Technetium Scan
This will show an increased uptake in Graves' disease.

4. Thyroid Antibodies
Autoantibodies against microsomal thyroid cell antigens are present in 90% of cases.