Permanent neonatal diabetes mellitus (PNDM) is defined as an diabetes mellitus that starts within the first six month of life. Antenatal growth retardation, hyperglycemia, glycosuria, osmotic polyuria, severe dehydration, and failure to thrive are commonly accompanying features. Several genes are involved in PNDM. Inheritance is autosomal dominant (KCNJ11 and INS), autosomal dominant or recessive (ABCC8), and autosomal recessive (GCK and PDX1).