Abstract :
We reported cases of Graves’ ophthalmopathy who presented solely with symptoms of the eyes and normal thyroid function tests, negative TSH receptor autoantibody (TRAb). These cases were referred to our hospital for unilateral or bilateral eye swelling with painful eye movements, with or without double vision, without any signs or symptoms of hyper- or hypothyroidism. Serum thyroid function tests and 99mTc uptake studies were within the normal range. Anti-thyroid autoantibodies (TRAb) were negative in all the cases. Since orbital CT scan and MRI gave typical results compatible with Graves’ ophthalmopathy and after exclusion of other possibilities, these patients were treated with corticosteroid pulse therapy and orbital radiation therapy, leading to a partial improvement of the symptoms. We followed up those cases with serial thyroid profile testing and TRAb estimation and they were subsequently developed clinical & biochemical hyperthyroidism within the next 18 months follow-up. At that time, they also became TRAb positive. These cases give us insight into the potential pathophysiologic mechanism underlying Graves’ ophthalmopathy and cast light upon the difficulties of establishing the diagnosis in biochemically euthyroid & thyroid autoantibody negative cases. Clinicians should be aware of the variable temporal relationship between the clinical expression of thyroid dysfunction and orbital disease in the natural course of Graves’ disease.
Keyword :
Graves’ ophthalmopathy, Thyroid receptor Antibody(TRAb).