Natural history of a pediatric cohort with islet autoantibody positivity: a single-center retrospective cohort study.

Context: Type 1 diabetes (T1D) progresses from genetic risk to metabolic disease. Anti-β-cell antibodies (AABs), alongside clinical features, define the stages of T1D and enable identification of presymptomatic individuals. Objective: To describe the natural history of patients with ≥1 positive AAB, analyzing progression to stage 3 T1D and clinical severity at diagnosis. Design: Single-center retrospective cohort study (February 2012-April 2025). Patients: One-hundred and six patients with ≥1 AAB-positive enrolled in a structured follow-up program. Main outcome measure: progression to stage 3 T1D and occurrence of diabetic ketoacidosis (DKA) at diagnosis. Results: = .0063) and remained independently associated with T1D onset in multivariable analysis. Conclusion: Persistent autoantibody positivity, particularly for GAD, is strongly associated with progression to stage 3 T1D. Children identified through AAB monitoring show a milder clinical presentation at diagnosis, with no cases of DKA. These data support screening and structured follow-up of at-risk children, which may help prevent DKA and facilitate identification of candidates for disease-modifying interventions.