Congenital non-neoplastic nevus

This code represents a birthmark that is present at birth or develops shortly thereafter, characterized by an abnormal growth of skin cells that is not cancerous. These nevi are typically benign and can vary in size, shape, and color, often appearing as moles or patches on the skin. They are distinct from acquired nevi, which develop later in life.

Use this code when documentation clearly identifies a nevus as congenital and non-neoplastic. This applies to conditions such as nevus sebaceus, nevus flammeus (port-wine stain), or other congenital vascular or epidermal nevi that are not classified elsewhere. Supporting documentation should specify the congenital nature of the nevus and confirm its benign status.

• Differentiate congenital nevi from acquired nevi; acquired nevi are typically coded to D22.-.
• Carefully review documentation to ensure the nevus is explicitly stated as non-neoplastic to avoid miscoding with malignant or uncertain behavior lesions.
• Be mindful of the "Excludes2" list to avoid coding common benign pigmented lesions like café au lait spots or lentigo to this code.