Background: Transient neonatal diabetes mellitus (TNDM) is a rare genetic β-cell dysfunction leading to hyperglycaemia that resolves in early childhood. About 80% of patients relapse during adolescence or adulthood. Some of these patients suffer from neurodevelopmental defect. Long-term outcome has been poorly investigated.
Objective and Hypotheses: To investigate metabolic and neurologic outcomes in adults affected with TNDM.
Method: The patients originated from the French Neonatal Diabetes Study Group cohort. We selected those with TNDM who were 18 years or more in September 2013. We assessed data on their glucose metabolism and neurodevelopmental outcomes from the medical reports and direct interviews.
Results: We included 24 individuals (seven males and 17 females). We identified 6q24 abnormalities (n=8, 33%), mutations in ABCC8 (n=8, 33%) and KCNJ11 (n=4, 17%) genes. 4 (17%) patients had no identified molecular defect. 23 (96%) patients relapsed their diabetes at a median age of 14.7 years (9.045.5). Mode of recurrence, detailed for 18 patients was polyuriapolydipsia (n=8), hyperglycaemia without ketoacidosis during an infectious disease (n=4) and during follow-up (n=6). Follow-up median duration after recurrence was 11.9 years (2.340.7) and median HbA1c after relapse 6.6% (5.813%). After recurrence, treatments were insulin (n=13), oral antidiabetic drugs (n=8) or both (n=2). Despite frequent observance failure (treatment stopped, n=5 and frequent oversight, n=6), only one patient suffered from ketoacidosis. Long-term diabetes complications occurred (retinopathy, n=3 and nephropathy, n=1). Neurodevelopmental outcomes revealed academic difficulties (n=12, 50%, who repeated a class at least once before the age of 16 years), difficulties interfering with reading achievement (n=8) and spatial disabilities (n=7), whatever the molecular aetiologies.
Conclusion: Our study suggests a partial insulin secretion defect in adulthood and a high incidence of neurodevelopmental difficulties. These results underscore the importance of performing a complete clinical and biological evaluation throughout adulthood in all patients affected with TNDM.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology