Childhood type 1 diabetes mellitus and gut microbiota: from microbiome characteristics to prevention and treatment strategies.

Type 1 diabetes mellitus (T1DM) in children is a chronic metabolic disease mediated by autoimmune abnormalities, characterized by extensive destruction and impairment of pancreatic islet β-cells, and represents a common chronic endocrine disorder in childhood. The occurrence and progression of T1DM are closely associated with genetic susceptibility and environmental factors. Compared with healthy children, children with T1DM exhibit a disrupted gut microecological balance, characterized by a marked reduction in microbial diversity, structural disturbances in dominant microbiota, and concomitant abnormalities in multiple metabolic pathways. Recent studies have indicated that the gut microbiota, as a key environmental factor, is associated with the pathophysiological processes of pediatric T1DM through mechanisms including altered intestinal permeability and modulation of immune homeostasis. This article provides a comprehensive narrative review of the characteristics of the gut microbiota in children with T1DM, summarizes current evidence regarding microbiome alterations and their underlying mechanisms, and discusses emerging microbiota-targeted interventions. The aim is to provide new insights for the early prevention, control, and clinical management of T1DM in children.