Utility of systematic TSHR gene testing in adults with hyperthyroidism lacking overt autoimmunity and diffuse uptake on thyroid scintigraphy.

Activating TSHR mutations are a rare cause of nonautoimmune adult hyperthyroidism. Our study does not support the routine genetic testing in adult patients with hyperthyroidism showing diffuse uptake on scintigraphy but negative TRAb and lacking extrathyroidal manifestations of Graves' disease.