Partial remission in Brazilian children and adolescents with type 1 diabetes. Association with a haplotype of class II human leukocyte antigen and synthesis of autoantibodies

Objective Characterization of partial remission using the insulin dose-adjusted HbA1c (IDAA1c) <= 9 definition in a multiethnic Brazilian population of children and adolescents with type 1 diabetes (T1D), in addition with the determination of both Class II HLA genotype and autoantibodies. Methods We analyzed the prevalence of partial remission in 51 new-onset T1D patients with a median time follow-up of 13 months from diagnosis. For this study, anti-GAD65, anti-IA2 and HLA class II genotyping were considered. Results Partial remission occurred in 41.2% of T1D patients until 3 months after diagnosis, mainly in those aged 5-15 years. We have demonstrated a significant increase in the haplotypes of class II HLA DRB1*0301-DQB1*0201 in children and adolescents with a partial remission phase of the disease (42.9% vs 21.7% in non-remitters, P = .0291). This haplotype was also associated with the reduction of anti-IA2 antibodies production. Homozygote DRB1*03-DQB1*0201/DRB1*03-DQB1*0201 children had the lowest prevalence of IA-2A antibodies (P = .0402). However, this association does not correlate with the time of the remission phase. Conclusion Although the number of patients studied was reduced, our data suggested that the association between genetics and decrease in antibody production to certain islet auto-antigen may contribute, at least in part, to the remission phase of T1D.