DEND syndrome due to V59A mutation in KCNJ11 gene: unresponsive to sulfonylureas.

Heterozygous activating mutations of KCNJ11 (Kir6.2) are the most common cause of permanent neonatal diabetes mellitus (NDM), and successful glycemic control has been obtained in several cases with oral sulfonylureas (SU). We have verified a lack of clinical response for both glycemic control and neurological features in an infant with permanent neonatal diabetes mellitus and DEND syndrome due to a V59A mutation in the KCNJ11 gene. Thus, our case reinforces that most cases with DEND syndrome are insensitive to SU.