Early-Onset Type 1 Diabetes Mellitus in Children: A Critical Review of Pathogenesis, Epidemiology, Clinical Management, and Emerging Therapeutic Strategies

Abstract

Early-onset type 1 diabetes mellitus (T1DM) in children is one of the most prevalent and clinically complex chronic autoimmune diseases of childhood, defined by progressive immune-mediated destruction of pancreatic beta cells, absolute insulin deficiency, and lifelong management demands. This critical narrative review synthesises current evidence on the global epidemiology, aetiopathogenesis, pre-clinical staging, clinical presentation, management, complications, and emerging preventive and therapeutic strategies for T1DM in the paediatric population. Global incidence is rising at an estimated 3–4% per year, with consistent trends towards younger age at presentation and considerable regional heterogeneity. Disease aetiology is multifactorial, involving HLA-driven genetic susceptibility, autoreactive T-cell-mediated insulitis, and environmental modifiers including viral infections, dietary exposures, and gut microbiome perturbations. The formal three-stage model of pre-clinical T1DM, defined by islet autoantibody profiles and dysglycaemia, has transformed disease understanding and created opportunities for targeted intervention before clinical onset. Contemporary management is increasingly technology-driven, with automated insulin delivery systems combining continuous glucose monitoring and insulin pump therapy demonstrating meaningful improvements in glycaemic outcomes for children. The COVID-19 pandemic has introduced an additional epidemiological layer, with SARS-CoV-2 infection associated with increased rates of new-onset T1DM and diabetic ketoacidosis at presentation. Teplizumab, an anti-CD3 monoclonal antibody, has become the first approved disease-modifying therapy capable of delaying clinical onset in high-risk individuals, marking a paradigm shift in T1DM prevention. Psychosocial burden on affected children and their families remains substantial yet under-addressed. Critical appraisal of the literature reveals persistent gaps in universal screening, equitable technology access, and long-term preventive trial data, particularly in low- and middle-income country settings.