Type 1 diabetes-related epidemiological, clinical and laboratory findings. An evaluation with special regard to autoimmunity in children.

OBJECTIVE To evaluate our data related with epidemiologic features, clinical presentation, and laboratory findings in children with type 1 diabetes mellitus (DM1) and to compare specific characteristics of immune-mediated subtype (DM 1A) with idiopathic one (DM 1B). METHODS We classified 115 children with DM1 according to the presence (DM 1A, n=77) or absence (DM 1B, n=38) of diabetes-related autoantibodies in Akdeniz University Hospital, Turkey from January 2000 to December 2005. RESULTS A total of 43 patients (37%) in the whole group, had onset of DM1 during the winter months and the lowest frequency occurred in summer (p<0.005). The duration of breast-feeding, introduction time of cow's milk, and seasonal distribution of birth-month or onset of disease did not significantly differ in both groups. When compared with patients who had no documented honeymoon period, the patients who had a documented honeymoon period had lower HbA1c levels (p<0.01) at the onset. A large percentage of patients with DM 1A were positive for glutamic acid decarboxylase antibody (GAD65). CONCLUSION There was no significant difference between patients with DM 1A and DM 1B with respect to epidemiologic features, and clinical presentation suggested that these factors do not play a major role either in creating a disease-initiating effect or in the development of islet autoimmunity. However, determination of GAD65 with HbA1c levels at the onset of the disease may ensure some useful information regarding clinical course.