Marine-Lenhart Syndrome

This episode explores Marine-Lenhart syndrome, a rare variant of thyrotoxicosis where Graves disease and autonomous thyroid nodules coexist within the same gland. We examine the dual mechanism of thyrotropin receptor activation, contrasting extrinsic antibody stimulation with permanent, somatic mutations. The discussion covers the clinical challenges this creates, including the classic scintigraphic unmasking of nodules, resistance to standard radioiodine therapy, and the compounding malignancy risks that make total thyroidectomy a preferred definitive management strategy.