Mild Thyrotoxicosis due to Seronegative Graves’ Disease or Disseminated Thyroid Autonomy

This case highlights the complexity of distinguishing DTA, seronegative Graves' disease and typical Graves' disease with initial false negative testing. A systematic approach with repeat testing and, when feasible, biopsy, is critical to distinguish these entities. Further studies with histologic analysis are needed to clarify outcomes and develop tailored managements, as these conditions have different remission rates and are driven by different mechanisms.