Autoimmune Polyglandular Syndrome II: A Case Report

Autoimmune polyglandular syndrome II (APS-II), also known as Schmidt syndrome, is a rare endocrine disorder characterized by endocrine and non-endocrine illnesses. Addison's disease and at least one additional autoimmune condition, such as autoimmune thyroid disease or type 1 diabetes mellitus (T1DM), are features of APS-II. It can result from genetic and non-genetic factors. We present a case of a 60-year-old female patient with a history of T1DM and a recent diagnosis of Hashimoto's thyroiditis who was admitted to the nephrology department for hyponatremia. Investigations showed the presence of adrenal insufficiency (AI), so she was diagnosed with APS-II and had the full triad of this syndrome. Thus, it is important to think about the diagnosis of AI or other autoimmune conditions in a patient who already has one or more autoimmune diseases.