Unsuccessful switch from insulin to sulfonylurea therapy in permanent neonatal diabetes mellitus due to an R201H mutation in the KCNJ11 gene: a case report.

Mutations in KCNJ11 are a common cause of permanent neonatal diabetes mellitus. Previously, all patients carrying an R201H mutation in the KCNJ11 gene showed successful switches from insulin to sulfonylurea. Here, we report an unsuccessful switch in an 18-year-old patient carrying the common R201H mutation in the KCNJ11 gene.