SAT-628 Navigating through the Challenges of Autoimmune Polyendocrine Syndromes

Abstract Disclosure: W. Akhter: None. S. Azmat: None. R. Akhter: None. A.J. Zaidi: None. J.L. Gilden: Novartis Pharmaceuticals. Introduction: Autoimmune polyendocrine syndromes (APS), which affect 1: 100,000 persons, consist of clinical conditions with impairment of multiple endocrine glands due to loss of immune tolerance. They are characterized by at least 2 or more endocrine diseases in a single patient with isolated endocrine dysfunction and later development of other endocrine and non-endocrine diseases. APS 1, the monogenic variety, includes Addison’s disease, chronic hypoparathyroidism and chronic candidiasis. APS-2 is a more common polygenic group with Addison’s disease, autoimmune thyroid disease and/or type 1 diabetes mellitus. APS-3 is characterized by autoimmune thyroid disease and other autoimmune diseases (excluding Addison’s disease and/or hypoparathyroidism). Patients frequently have other conditions (alopecia, vitiligo, celiac disease, and autoimmune gastritis). CASE PRESENTATION A 42-year-old male presented to the Endocrine clinic at the age of 40 for evaluation and management of symptomatic type 1 diabetes mellitus. Hemoglobin A1C >14% (Normal < or = 5.6%). Lipid panel showed elevations in LDL (213.7 mg/dL. Normal range 0-100 mg/dL) and Triglycerides (418 mg/dL. Normal range 0-150 mg/dL). Microalbumin/Cr ratio was 30.9 mg/g (Normal <=30). Initial laboratory: C peptide level 1.71 ng/mL (normal= 0.81-3.85 ng/mL), positive GAD antibodies (58 IU/mL; normal < 5 IU/mL) but negative islet cell and IA2 antibodies (<0.4. Normal <0.4 U/mL). Most recent labs showed conversion of islet cell antibodies to positive (Islet cell antibody titer 80 JDF units; normal IC titer < 1.25) in addition to positive GAD 65 antibodies (58 IU/mL, reference range < 5 IU/mL) and zinc transporter antibodies (18 U/mL, normal reference range <15 U/mL). Thyroid peroxidase was now 1193 U/mL (normal= 0-60 U/mL) and thyroglobulin antibodies (147 U/mL, normal= 0-60 U/mL). Other antibodies (intrinsic factor blocking antibodies, tissue transglutaminase antibodies (<1 U/mL, normal <15) AMA, anti-striated muscle antibodies and ANA) were negative. Conclusion: APS syndromes, characterized by circulating autoantibodies and lymphocytic infiltration of affected tissues and organs can eventually lead to organ failure. It is important to recognize that these syndromes can occur at any age, from early infancy to old age. Although, there is marked variation in the frequencies and patterns of autoimmunity, the risk for development of autoimmune disease is most likely due to a combination of genetic susceptibility and environmental factors. It is also recognized that these patients are at risk for adrenal crisis, hypoglycemia and DKA, among others. Therefore, patients with APS need to be followed closely due to the need for periodic evaluation, as well as complex management, which can be lifesaving. Furthermore, family members should also be tested periodically for organ specific antibodies. Presentation: Saturday, July 12, 2025