Early Recognition of Proteus Syndrome.

Proteus syndrome is an extremely rare mosaic condition characterized by progressive overgrowth of tissues due to a somatic activating mutation of the AKT1 gene. Distinct cutaneous features, including cerebriform connective tissue nevi, epidermal nevi, vascular malformations, and adipose abnormalities, can alert the dermatologist to the underlying condition before the onset of asymmetric skeletal overgrowth. We present a series of photographs documenting the skin and musculoskeletal changes in a patient with Proteus syndrome over the first 2 years of life to emphasize the key signs that a dermatologist can recognize to facilitate an earlier diagnosis in these patients.