ephelides

Ephelides, also known as freckles, are small, flat pigmented spots that commonly occur on sun-exposed skin. They most often appear in early childhood and are more common in people with fair skin, especially those with red or light hair. Freckles are typically found on the face, arms, and shoulders but can occur on any sun-exposed area. They vary in size from about 1 to 2 millimeters and range in color from pale brown to dark brown.

Pathophysiology and genetics: Freckles arise from localized increases in melanin production by melanocytes in response to ultraviolet radiation. This reflects an increase in pigment, not an increase in the number of melanocytes. The spots darken with sun exposure and often fade during winter when UV exposure decreases. Freckles have a genetic component and are more common in individuals with MC1R gene variants, contributing to the fair-skinned, red-haired phenotype.

Diagnosis and differential: Ephelides are diagnosed clinically and are usually benign. They should be distinguished from lentigines (liver spots), which are typically larger, darker, and do not fade with reduced sun exposure; lentigines involve more persistent changes in melanocyte activity and age-related factors.

Management: No treatment is required beyond sun protection, since freckles are benign and may reappear with sun exposure. Cosmetic options for those who wish to reduce their appearance include laser therapies or topical depigmenting agents, though results vary and freckles may recur with sun exposure.