Neonatal Diabetes Mellitus Due to Complete Glucokinase Deficiency

Abstract
Diabetes mellitus is a heterogeneous disorder that can occur at any age.1 Neonatal diabetes mellitus, defined as insulin-requiring hyperglycemia within the first month of life, is a rare disorder that is usually associated with intrauterine growth retardation.2 Like diabetes in general, neonatal diabetes is heterogeneous and can be either transient or permanent. Transient neonatal diabetes is associated with abnormalities of chromosome 6,2,3 whereas mutations in insulin promoter factor 1 result in pancreatic agenesis and permanent neonatal diabetes.4 We describe two patients in whom complete deficiency of the glycolytic enzyme glucokinase, a key regulator of glucose metabolism in pancreatic beta cells that couples extracellular glucose to insulin secretion, caused permanent neonatal diabetes.5