Glibenclamide unresponsiveness in a Brazilian child with permanent neonatal diabetes mellitus and DEND syndrome due to a C166Y mutation in KCNJ11 (Kir6.2) gene.

Heterozygous activating mutations of KCNJ11 (Kir6.2) are the most common cause of permanent neonatal diabetes mellitus (PNDM) and several cases have been successfully treated with oral sulfonylureas. We report on the attempted transfer of insulin therapy to glibenclamide in a 4-year old child with PNDM and DEND syndrome, bearing a C166Y mutation in KCNJ11.