Slow evolution of non-familial autoimmune polyglandular syndrome type II in a 54-year-old female, first presenting with Addison’s disease, then Hashimoto’s thyroiditis, which then transitioned to Graves’ disease and then the development of type 1 dia

<b>Autoimmune polyglandular syndrome type II is progressive and unpredictable</b> New endocrinopathies may develop years or even decades after the initial presentation, requiring lifelong surveillance.<b>Autoimmune thyroid disease can be dynamic</b> Although rare (~1% of cases), transitions from Hashimoto's hypothyroidism to Graves' hyperthyroidism are well documented and should be considered when thyroid function changes unexpectedly.<b>Clinical vigilance is crucial</b> Suppressed thyroid-stimulating hormone in a patient on levothyroxine is not always due to over-replacement; testing for thyroid-stimulating immunoglobulin should be considered to exclude evolving Graves' disease.<b>Adrenal insufficiency must be recognized before thyroid therapy</b> Initiating levothyroxine without adequate glucocorticoid coverage can precipitate adrenal crisis in autoimmune polyglandular syndrome type II.<b>Multidisciplinary care improves outcomes</b> Coordinated management between endocrinology, primary care, and other specialties ensures timely detection and treatment of evolving autoimmune conditions.