Ephelides (freckles) and lentigines, are important pigmentation characteristics observed in humans. Both are affected by sunlight; ephelides (freckles) are largely genetically determined but induced by sunlight, whereas lentigines are induced by sun exposure and photodamage of the skin. However, despite being commonly observed, we know very little about them. The following table summarize the main differences between ephelides and lentigines:
| Freckles (Ephelides) | Lentigines | |
| Age of onset | Early childhood
First visible at 2–3 years of age after sun exposure fade with age |
Middle age
Accumulate with age Common after 50 Stable |
| Skin type | Caucasians, Asians, skin type I-II.
Fair skin, especially with red or blond hair and blue eyes. |
Caucasians, Asians, skin type I–III |
| Areas affected | Face, neck, chest, arms | Sun-exposed skin, face, hands, forearms, chest back and shins |
| Size | Small flat pigmented macules
1–2 mm and above |
Larger than freckles
mm-cm in diameter |
| Borders | Irregular, well defined | Well defined |
| color | Red to light brown | Light yellow to dark brown |
| Numbers | Few to hundreds | Few to hundreds |
| Duration | Fade with age | Persist for life |
| Relation to season | Are more prominent in summer but fade considerably or disappear in winter | Stable
don’t disappear in the winter |
| Etiology | Genetic | Environmental |
| Melanocyte number | More | 1–2.2 times more |
| Melanocyte size | Large, more dendrites | Normal |
| Melanosome number | Increased | Normal |
| Melanosome size | Larger | Normal |
| Epidermal rete ridges | Elongated | Elongated |
| Epidermal pigmentation | Increased | Increased |
| Other | Melanin-laden macrophages | Melanosome complexes in keratinocytes
More mitochondria Better-developed ER Microinvaginations into keratinocytes ‘Pendulum melanocytes’ |
| Treatment | Apart from sun protection, no particular treatment is necessary. | Cryotherapy
Laser surgery creams that include retinoids and bleaching agents in them |
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