ESPE Abstracts

Background: Diabetes mellitus (DM) in childhood was mostly type 1 DM (T1DM), but sometimes it is not easy to classify, especially in the case having both type 2 clinical phenotype and autoantibody positivity. It is named as latent autoimmune diabetes in youth or type 1.5 DM (T1.5DM).

Objective and hypotheses: This study was designed to evaluate the clinical characteristics of T1.5DM who had autoantibody positivity with clinical phenotype of T2DM.

Method: Ninety five subjects who were diagnosed as having DM between 2001 and 2015 were enrolled in the study. Subjects with fulminant diabetes or less than 6 months of follow-up, or no assessment of autoantibody status were excluded. Study subjects were classified into type 1, 1.5, and 2 DM. Clinical features as well as laboratory findings were compared between groups.

Results: Among 95 subjects, type 1.5, 1, and 2 DM were 11 (11.6%), 51 (53.7%), and 33 (34.7%), respectively. In T1.5DM, age at diagnosis and BMI Z scores were significantly higher compared to T1DM, and there was no DKA at initial presentation. Serum c-peptide levels were higher compared to those in T1DM (2.28±1.42 ng/ml vs. 0.52±0.44 ng/ml, P<0.001). The titers of anti IA-2 autoantibody were significantly lower in T1.5DM compared to T1DM (4.86 vs. 45.95 U/mL, P<0.001). During mean follow-up of 3.22 years in T1.5DM, 27% turned autoantibody negative, and 25% of the subjects who had persistently positive autoantibody needed intensive insulin treatment of more than 0.5 U/kg per day.

Conclusion: In T1.5DM, it may be necessary to recheck autoantibody, especially in patients who initially had weakly positive autoantibody titer. It is important to closely monitor patients with T1.5DM because they might need intensive insulin treatment within several years.