ESPEYB18 2. Antenatal and Neonatal Endocrinology Neonatal diabetes mellitus (5 abstracts)
Eur J Endocrinol. 2021 Apr;184(4):575585. doi: 10.1530/EJE-20-1030. PMID: 33606663.
These authors examined the likelihood of remission of diabetes without pharmacological therapy in a retrospective analysis of 34 Italian patients with Transient neonatal diabetes (TNDM).
TNDM is a type of neonatal diabetes that remits within the first a few months of life. It is most commonly due to either mutations in the ABCC81/KCNJ11 genes or abnormalities in chromosome 6q24. The underlying mechanisms of hyperglycaemia differ by the cause. Mutations in ABCC81/KCNJ11 lead to dysfunction of the pancreatic KATP channel which regulates the beta-cell membrane permeability and thus insulin secretion. In contrast, the mechanism of defective insulin secretion due to abnormalities in chromosome 6q24 is not known but might involve changes in the expression of imprinted genes (such as PLAGL1 and HYMA1) leading to alterations in islet organogenesis. Patients with TNDM due to ABCC81/KCNJ11 mutations and abnormalities in chromosome 6q24 have distinct clinical and biochemical features. Those with chromosome 6q24 abnormalities have lower birth weights, present early, are less likely to have diabetic ketoacidosis, and diabetes will spontaneously remit but then relapse again around adolescence. Important clinical clues in infants with TNDM due to 6q24 abnormalities are umbilical hernia and macroglossia. More importantly from the therapeutic perspective, infants with ABCC81/KCNJ11 mutations must be diagnosed as early as possible as they will respond to oral sulphonylureas and insulin injections can be stopped. Thus, patients with TNDM should be screened as early as possible for ABCC81/KCNJ11 mutations (except those with obvious macroglossia and umbilical hernia who should be tested first for 6q24) as this might have important treatment implications.