Ephelides (colloquially called freckles; ephelides: Greek ἔφηλις – ephelis, in plural ephelides from Gr. epi – ἐπί “at” and hēlios – ἥλιος; synonyms: summer spots; in Austria also Gugerschecken/Gugaschecken or Guckerschecken, in Switzerland also Märzen- or Laubflecken; ICD-10 L81.2.: ephelides. Incl: Freckles) are more pigmented, small yellowish and brownish spots on the skin. They occur, especially on sun-exposed areas of the skin, such as the face or arms.People with reddish-blond hair and fair skin are particularly often affected.Redheaded people exhibit increased melanin synthesis. This means that more pigments are formed, which appear concentrated in patches. Likewise, the number of melanocytes (pigment-forming cells) is increased.
Ephelides occur mainly on the face, arms and shoulders, and neckline.
Course and prognosis: Usually freckles fade in winter and do not reappear clearly until summer.Freckles can reappear at any time. This cannot be prevented. The only thing that can be done is to protect the skin from the sun with suntan lotion or similar products in order to form as few freckles as possible.
Differential diagnoses
- Lentiginosis – congenital or acquired (multiple) pigment mottling of the skin and/or mucosa.
- Verrucae planae juveniles (plane juvenile warts; flat warts).
- Xeroderma pigmentosum (synonyms: Melanosis lenticularis progressiva, also moonshine disease or light shrinkage skin, “XP” for short) – genodermatosis (skin disease based on a genetic defect), which is assigned to the chromosome break syndromes.
Pathogenesis (disease development) – etiology (causes)
The predisposition to freckles is genetic. They are caused by congenital gene variants in the melanocortin-1 receptor, which is also responsible for skin and hair color.
Freckles are caused by melanocytes that produce increased melanin (hyperpigmentation). The melanin is stored in the surrounding keratinocytes (horn-forming cells) for some time.
Therapy
The most important measure is consistent UV protection.
If necessary, cover, e.g., with hydrophilic skin-colored concealer.