Autoantibody positive versus autoantibody negative type 1 diabetes in children: clinical and biochemical characteristics

Introduction. This study aimed to investigate differences in clinical and biochemical characteristics between autoantibody positive and autoantibody negative type 1 diabetes mellitus (T1DM) in children, to get a better understanding of autoantibody negative T1DM. Methods. This study is a mono-center retrospective cross-sectional cohort study conducted at Diaboss, a Dutch pediatric diabetes clinic at OLVG hospital. Patients diagnosed with T1DM before the age of 18 years were included. Patients tested positive for one or more diabetes-associated autoantibodies (GADA, IA2A, ZnT8, IAA and/or ICA) were considered autoantibody positive. Results. 562 patients were recruited. Eight of 562 (1,4%) patients tested positive for a monogenic cause of diabetes at a later stage and were excluded. In 15 of 66 patients (23%) with autoantibody negative T1DM, monogenic causes were ruled out by genetic testing. The other 51 patients (77%) were not tested. Autoantibody negative patients with a positive family history for diabetes were more likely to be tested for monogenic causes (P=0,002). No significant differences in demographic and clinical characteristics, diabetes presentation and long-term diabetes regulation were found between autoantibody positive and autoantibody negative patients. Conclusion. In our study, autoantibody positive and negative T1DM patients were similar. This implies that both patient groups can be approached in the same way regarding treatment, education and prognosis. Misdiagnosis of monogenic causes within T1DM could occur, therefore clinicians should be aware and perform genetic tests according to international guidelines.