IMPE Abstracts

Introduction: 6q24-related transient neonatal diabetes mellitus (6q24-TNDM) is defined as transient neonatal diabetes mellitus caused by genetic aberrations of the imprinted locus at 6q24. The cardinal features are: severe intrauterine growth retardation, hyperglycemia that begins in the neonatal period in a term infant and resolves by age 18 months, dehydration, and absence of ketoacidosis.

Objectives: In this presentation we want to show the evolution and outcome of a patient that was diagnosed in our unit 15 years ago as well as the importance of a proper genetic counseling made on the basis of the error found during diagnosis. It is important to highlight the need to study the parental imprinting error in order to make this proper genetic counseling.

Methods: The initial diagnosis was made using microsatellites looking for a paternal isodisomy or duplication. An isodisomy was found in our case. We have made a follow up throughout these years to see the evolution of our patient.

Results: The patient stopped needing insuline at the age of 9 months old and has been absolutely asymptomatic until she was 12 years old. Just 20 months ago (at the age of 13) she started to show abnormal HbA1C levels (7,2%) that has required insulin treatment. Nowadays she is having a perfect control of this new-onset diabetes using really low dose of Insulin glargine. Just 0,28U/kg are being needed to keep the blood sugar levels in range in 90% of readings. The patient is not needing so far rapid acting insulin. A change in treatment is being offered nowadays to the family. It is planned to start with glibenclamide in the near future.

Conclusions: 6q24- related transient neonatal diabetes can have a relapse in the second or third decade of life in 50% of cases. It is important to know this is not a tipical type 1 or 2 diabetes. So far this relapse is having a very good outcome using low doses of insulin glargine. The chances that the baby’s parents will have another child with TNDM are very low (<1%). Furthermore, it is very unlikely that a baby with TNDM caused by uniparental disomy will have a child with TNDM.