Slowly developing immune-mediated diabetes, often called latent autoimmune diabetes in adults, is characterized by the presence of autoantibodies (ATs) to glutamic acid decarboxylase (GADA), the patient's age at the onset over 35 years, and the absence of the need for insulin therapy for 6-12 months to 6 years from the moment of diagnosis, according to the WHO classification of 2019, refers to hybrid forms of diabetes mellitus (DM). In this article, we present a case history of slowly developing immune-mediated diabetes in a 14-year-old boy who was transferred from metformin monotherapy and a diet with restriction of digestible carbohydrates to the intensified insulin therapy only 4 years after the onset of diabetes mellitus with a glycated hemoglobin (HbA1c) level of less than 6.5% throughout the disease. As a result of the studies, the patient was found to have a homozygous genotype highly predisposing to the development of Type 1 Diabetes Mellitus (T1DM), as well as increased levels of ATs to GADA and tyrosine phosphatase (IA-2A). The initially preserved level of basal C-peptide and the clinical course of the disease in this patient do not allow us to classify this case as a classic variant of the course of Type 1 Diabetes Mellitus.
The glutamic acid decarboxylase 65 immunoglobulin G subclass profile differs between adult-onset type 1 diabetes and latent autoimmune diabetes in adults (LADA) up to 3 years after clinical onset
