Nevus Simplex (aka Salmon Patch)

Nevus simplex is now the preferred term for the most common vascular birthmark of infancy formerly known as the salmon patch.
A nevus simplex is evident at birth as a pink-red vascular patch in characteristic locations on the face or on the occipital scalp.

Pathogenesis ⬆ ⬇

Etiology is unknown.
Many experts believe it to be a form of persistent fetal circulation rather than a true vascular malformation.

Clinical Manifestations ⬆ ⬇

A nevus simplex presents as an ill-defined, flat, dull pink or red, blanchable patch most commonly on the posterior scalp (aka “stork bite”), glabella (aka “angel's kiss”), forehead, upper eyelids, nose, and/or upper lip (Figs. 1.8 and 1.9).
Less often, a nevus simplex can have a more extensive, widespread distribution.
Lesions become deeper red with crying and physical exertion.
Complete resolution within the first 2 years of life is expected for >95% of lesions on the face.
Occipital lesions tend to persist for longer, some indefinitely.

Diagnosis ⬆

Differential Diagnosis

Port-Wine Stain

Early Hemangioma

Management

No treatment is necessary as the vast majority of lesions on the face fade completely.
More extensive lesions and occipital lesions can persist beyond the first year of life.
Pulsed dye laser (PDL) is effective for persistent lesions.

Helpful Hints

Nevus simplex are common, occurring in 30% to 40% of newborns.
Nevus simplex should be distinguished from a port-wine stain (PWS) early on so parents can be reassured of their eventual resolution and lack of associated findings.