SAT-603 Progression from Stage 1 to Stage 3 Type 1 Diabetes with Predominant Hypoglycemia

Abstract Disclosure: A.N. Nagarapu: None. J.L. Felton: None. Type 1 diabetes (T1D) is a chronic disease that progresses through well-defined stages. T1D begins in stage 1, which is defined by the presence of multiple islet autoantibodies and normal glucose tolerance. Progression to stage 2 is defined by the development of abnormal glucose tolerance, and stage 3 is defined by overt and symptomatic hyperglycemia, typically necessitating insulin initiation. Here, we present a case of a 9-year-old male with rapid progression from stage 1 to stage 3 characterized by multiple episodes of hypoglycemia. The patient presented to the emergency department (ED) when his mother was concerned that polyuria and polydipsia over the last several months suggested the development of T1D. In the ED, random glucose was 147 mg/dL (8.16 mmol/L) and HbA1c was 5.7%. Given the slightly elevated HbA1c, islet autoantibodies were ordered and he was scheduled for a follow-up outpatient oral glucose tolerance test (OGTT). However, prior to obtaining the OGTT, he returned to the ED after an episode of hypoglycemia at home (30 mg/dL (1.67 mmol/L), on home glucometer) that was treated prior to arrival in ED. Work-up at that time revealed trace ketones and repeat HbA1c of 5.4%. Islet antibody testing also revealed positive GAD and IA-2 antibodies, consistent with a diagnosis of stage 1 T1D. When he continued to have symptoms of hypoglycemia at home, he was admitted for a 24-hr controlled fast, which revealed ketotic hypoglycemia. He received nutritional counseling and was started on a continuous glucose monitor (CGM) at that time. Glucose data was reviewed one month later and demonstrated an average glucose of 112 mg/dL (6.22 mmol/L) with 94% glucoses within range (reference range 70-180 mg/dL, 3.89-9.99 mmol/L). 3 weeks later, he returned to the ED for persistent hyperglycemia (>300 mg/dL (16.65 mmol/L)), and CGM data showed a 14-day average glucose of 160 mg/dL (8.88 mmol/L) and only 45% glucoses within range. HbA1c at that time was 6.1%, consistent with stage 2 T1D, though post-prandial glucoses at home were consistent with stage 3 T1D. This case demonstrates an extremely rapid progression to symptomatic hyperglycemia that was heralded by multiple episodes of hypoglycemia. This case adds to the growing body of evidence for true hypoglycemia during early stages of T1D progression and supports further exploration of hypoglycemia in early stage T1D as a biomarker for risk for rapid progression. Presentation: Saturday, July 12, 2025