Common Skin Conditions in Children: Congenital Melanocytic Nevi and Infantile Hemangiomas.

Congenital melanocytic nevi (CMN) are hamartomas present at birth that are composed of nevomelanocytes and thought to originate from faulty migration of precursor melanocytes in the neural crest. Classification is based on projected adult size of the lesion. CMN size correlates positively with risk of melanoma and neurocutaneous melanocytosis. Management requires a patient-centered approach that weighs the risks and benefits of and alternatives to complete removal. All children with large and giant CMN, regardless of surgical status, should be monitored closely and undergo periodic skin examination. Infantile hemangiomas (IHs) are vascular neoplasms arising from endothelial cell hyperplasia that go through proliferative (growth) and involutional phases. Large, segmental IHs carry a higher risk of bleeding, and patients with these IHs may benefit from imaging. Small, focal IHs in noncritical areas do not require treatment. In contrast, early referral and treatment should be considered for patients with large, extensive, deep, segmental, or syndromic IHs. Systemic and topical beta blockers have the strongest efficacy data and have replaced systemic and intralesional corticosteroids as first-line treatment for IHs in the United States. Surgical therapies are second-line modalities, with laser treatment being used most widely.