Determination of the levels of anti-thyroid-stimulating hormone receptor antibody with thyroid peroxidase antibody in Omani patients with Graves' disease.

OBJECTIVE To determine the levels of anti-thyroid-stimulating hormone receptor antibody (TRAb) and thyroid peroxidase antibodies (TPO) in Omani patients with Graves' disease (GD). SUBJECTS AND METHODS ELISA was used to measure the levels of TRAb and TPO in sera of 111 patients with GD, 40 patients with systemic lupus erythematosus (SLE) and 50 healthy normal subjects. Seventy-eight GD patients received iodine-131 treatment while 33 newly diagnosed patients did not receive any treatment. RESULTS The levels of TRAb in the patients with GD, SLE and normal subjects were 7.24 9+/-0.623, 1.04+/-0.179 and 0.539+/-0.070 units/liter, respectively. Elevated levels of TRAb were found in 75, 5 and 2% of patients with GD, SLE and normal subjects, respectively. For anti-TPO antibodies, the levels were 713.331+/-97.905, 85.575+/-34.936 and 22.96+/-4.544 lU/ml, for patients with GD, SLE and normal subjects, respectively. The elevated level of anti-TPO antibodies were found in 72, 15 and 6% of patients with GD, SLE and normal subjects. Statistically significant differences in positive levels of TRAb and anti-TPO antibodies were found in patients with GD as compared to SLE and normal subjects (p<0.001). The treated GD patients had lower levels of TRAb than untreated, but no difference was detected in the levels of anti-TPO antibodies between the treated and not treated. CONCLUSION High levels of TRAb and TPO were detected in Omani patients with GD. TRAb may be helpful in the diagnosis and monitoring the efficacy of iodine-131 treatment in GD patients.