Neonatal diabetes mellitus

This code signifies a rare form of diabetes diagnosed within the first six months of life, characterized by hyperglycemia requiring insulin or other glycemic control measures. It results from genetic defects affecting pancreatic beta-cell function or development, distinct from type 1 or type 2 diabetes.

Apply this code when documentation clearly indicates a diagnosis of diabetes mellitus in a neonate (birth to 28 days) or infant up to six months of age. Supporting documentation should include laboratory confirmation of hyperglycemia and the age of onset.

• Differentiate from transient neonatal diabetes, which often resolves spontaneously.
• Do not confuse with congenital diabetes, which is a broader term and may not specifically refer to the neonatal period.
• Always sequence as the primary diagnosis when it is the reason for the encounter.