ESPE Abstracts

Background: Diabetes mellitus is not characteristic of Beckwith Wiedeman Syndrome (BWS). If anything, BWS is associated with hypoglycaemia secondary to hyperinsulinaemia. A case of permanent neonatal diabetes mellitus and BWS have never been reported from our setting.

Objective and hypotheses: To report on a 17 years old boy with BWS diagnosed with permanent neonatal diabetes mellitus at 4 months of age and to determine the molecular genetics study which may associated with diabetes and BWS.

Method: He was a term baby, weighing 5.25 kg, born by caesarian section (CS) for cephalo-pelvic disproportion. He had earlobe crease, protruded tongue and omphalocoele requiring immediate surgical repair. He stayed in-patients for 2 months post operation. He suffered recurrent hypoglycaemia until 4 months of age, and then developed persistently elevated glucose requiring insulin therapy. He was tested for DNA methylation at the imprinted KCNQ1OT1/H19 loci and PLAGL1 locus as well as the sequence analysis of coding and flanking intronic regions of the ABCC8 and KCNJ11 gene.

Results: In addition to the clinical features of protruding tongue, macrosomia, omphalocoele, earlobe creases and persistent hyperglycaemia requiring insulin, his DNA showed complete hypomethylation at KCNQ1OT1. His DNA methylation was normal at H19 and the TND locus. There was no mutations detected in the KCNJ11 and KIR6.2 genes. The complete hypomethylation at KCNQ1OT1 is consistent with a diagnosis of BWS and the normal methylation at H19 is inconsistent with paternal uniparental disomy at chromosome 11. The absence of KCNJ11 and KIR6.2 is inconsistent with a diagnosis of neonatal diabetes. The combination of clinical signs with molecular genetic studies confirms the diagnosis of BWS in our patient, however, the mutational analysis of the K-ATP channels fails to confirm the cause of diabetes mellitus.

Conclusion: Diabetes mellitus in BWS occurs rarely and future studies should aim to identify possible causes of diabetes in BWS.