SAT-610 Unmasking Autoimmunity: Diabetic Ketoacidosis As The Initial Presentation Of LADA Triggered By Thyrotoxicosis

Abstract Disclosure: A. Farid: None. M. Almas: None. O. Adi: None. S. iqbal: None. M. Saadaldin: None. Introduction: Diabetic ketoacidosis (DKA) is a life-threatening complication of diabetes mellitus, commonly triggered by infection, noncompliance, or new-onset diabetes. Rarely, endocrine conditions such as thyrotoxicosis may unmask latent autoimmune diabetes [1]. Thyrotoxicosis can worsen hyperglycemia through increased insulin resistance, gluconeogenesis, and lipolysis [2]. This case highlights the interplay between thyrotoxicosis, pancreatitis, and autoimmune diabetes presenting as DKA. Clinical case: A 39-year-old woman with no significant past medical history presented with six days of nausea, vomiting, diarrhea, and epigastric pain radiating to the back, alongside a three-month history of polyuria, polydipsia and unintentional weight loss. She denied steroid use or a family history of diabetes. On examination, the patient was tachycardic with a heart rate of 110 bpm, while other vital signs remained stable. Labs showed glucose 960 mg/dL, HbA1c 11%, Na 121 mmol/L, bicarbonate 12 mmol/L, β-hydroxybutyrate 3.5 mmol/L, and 3+ glucosuria—consistent with DKA. Additional findings included triglycerides 709 mg/dL, mildly elevated lipase (89 U/L), ALP 287 U/L, and lactic acid 2.4 mmol/L. She was started on IV insulin and transitioned to a basal-bolus regimen. Ongoing tachycardia prompted thyroid workup, revealing suppressed TSH (<0.005 µIU/mL), elevated free T4 (3.97 ng/dL), T3 (14.61 pg/mL), and TPO antibodies (599 IU/mL), consistent with autoimmune-mediated hyperthyroidism. Thyroid ultrasound showed diffuse enlargement and hypervascularity. A TR4-rated nodule in the left mid-pole and a right focal lesion suggested focal thyroiditis. GAD65 antibodies were elevated (10,498 IU/mL), confirming autoimmune type 1 diabetes (LADA) [1]. The combination of hypertriglyceridemia, abdominal pain, and elevated lipase suggested acute mild pancreatitis [2]. She was treated with beta blockers and insulin, and discharged home in stable condition. A radioactive iodine uptake scan was planned outpatient. Conclusion: This case illustrates the rare presentation of latent autoimmune diabetes in adults (LADA) unmasked by thyrotoxicosis, with possible contribution from thyrotoxicosis-induced pancreatitis. Clinicians should consider thyroid dysfunction in unexplained DKA presentations, especially with persistent tachycardia or metabolic derangements. Early endocrine evaluation may guide comprehensive treatment and improve outcomes. References: 1. Hawa MI, Kolb H, Schloot N, et al. Adult-onset autoimmune diabetes in Europe is prevalent with a broad clinical phenotype: Action LADA 7. Diabetes Care. 2013;36(4):908-913. 2. Wang Y, Zhang M, Zhang P, et al. Thyrotoxicosis-induced diabetic ketoacidosis and acute pancreatitis in a patient with latent autoimmune diabetes in adults: A case report and literature review. Medicine (Baltimore). 2019;98(5):e14386 Presentation: Saturday, July 12, 2025