Neonatal Diabetes is a type of monogenic (single gene) diabetes, where a baby develops diabetes in the first six months of life. It is a rare disease (approximate incidence of 1:100,000 live births) that reflects severe β cell dysfunction. At this age, it is most likely to have a monogenic cause rather than being due to autoimmunity 1.
Monogenic diabetes results from an alteration in the genetic code and appear to occur all over the world. A team lead by Professor Hattersley and his colleagues at the University of Exeter in the UK have identified 15 distinct genetic types of diabetes1. Treatment decisions are based on the individual genes and tailored to the child/person.
The most common cause of neonatal diabetes are potassium channel gene mutations in the ABCC8 and KCNJ11 genes encoding. Correct function of the potassium channel is necessary for secretion of insulin in response to glucose levels. Approximately 40% of children/adults with neonatal diabetes have a potassium channel gene mutation which is sensitive to sulphonylurea(glibenclamide) treatment. In this subset glycaemic control can be greatly improved from switching by insulin to glibenclamide therapy. One such case was described in an 8-year-old girl in Togo, West Africa2. However, this genetic diagnosis must be made before insulin is stopped, and before the child/adult is switched to glibenclamide.
There are a number of other monogenic types, all of these require insulin. Some of the rarer types are also associated with congenital abnormalities. There is sometimes a family history, with an older sibling also having had neonatal diabetes.
Genetic testing
Genetic testing for neonatal diabetes is indicated, and now recommended in international guidelines for children/adults diagnosed with diabetes before 9 months of age regardless of their current age. Currently genetic testing finds a genetic diagnosis for over 85% of patients with neonatal diabetes1.
Genetic testing is supported in Exeter in the UK and can be provided free of charge. You can email Dr Elisa De Franco ([email protected]), explain your situation and ask if they can waive the fee. You can mention that you are a Life for a Child partner centre. LFAC may be able to help with the postage of samples - please ask us.
Please follow the instructions on blood sample collection and transportation on the University Exeter, Medical School ‘DiabetesGenes’ website.
If you have any questions or are not sure whether your patient should be tested for neonatal diabetes, please contact [email protected].
For clinical advice please contact Prof Andrew Hattersley by e-mail [email protected]
For further information and testing guidelines for diabetes subtypes and rare types of diabetes, visit the ‘DiabetesGenes’ website.
