Neonatal diabetes mellitus and organic acidemias, may present with similar 
features like hyperglycemia, ketoacidosis and failure to thrive. A four-mo-old 
girl presented with diabetic ketoacidosis following a febrile respiratory 
illness during which high anion gap metabolic acidosis and hyperglycemia were 
detected. She also had hyperammonemia, which led to diagnostic uncertainty. 
Euglycemia was achieved with insulin injections. Genotyping revealed a 
homozygous novel mutation of the ABCC8 gene coding for the SUR1 subunit of the 
pancreatic beta cell potassium channel. Subsequently, the child was successfully 
transitioned to oral glibenclamide therapy. Developmental delay was noted on 
follow-up which raised the possibility of intermediate DEND syndrome. A possible 
cause for hyperammonemia in neonatal diabetes mellitus has been postulated in 
the discussion.