Islet-cell associated antibodies are predictive and diagnostic markers for type 1 diabetes. We studied the differences in the early clinical course of children with type 1 diabetes with a single antibody and those with multiple antibodies against pancreatic β-cells. Sixty-seven children with type 1 diabetes aged less than 15 years diagnosed between 2010 and 2021 were included in the study and subdivided into two subgroups: children who were single positive for either glutamic acid decarboxylase (GAD) antibodies (n = 16) or insulinoma-associated antigen-2 (IA-2) antibodies (n = 13) and those positive for both antibodies (n = 38) at diagnosis. We compared the patients' clinical characteristics, pancreatic β-cell function, and glycemic control during the 5 years after diagnosis. All clinical characteristics at diagnosis were similar between the two groups. One and two years after diagnosis, children who tested positive for both antibodies showed significantly lower postprandial serum C-peptide (CPR) levels than those who tested positive for either GAD or IA-2 antibodies (p < 0.05). In other periods, there was no significant difference in CPR levels between the two groups. There was a significant improvement in glycosylated hemoglobin (HbA1c) levels after starting insulin treatment in both groups (p < 0.05), but no significant difference in HbA1c levels between the groups. Residual endogenous insulin secretion may be predicted based on the number of positive islet-cell associated antibodies at diagnosis. Although there are differences in serum CPR levels, optimal glycemic control can be achieved by individualized appropriate insulin treatment, even in children with type 1 diabetes.
Keywords: Glycosylated hemoglobin; Islet-cell associated antibodies; Japanese child; Serum C-peptide immunoreactivity; Type 1 diabetes.