Melasma (chloasma)
Overview
Plain-Language Overview
Melasma (chloasma) is a common skin condition that causes dark, patchy discoloration on the face, especially on the cheeks, forehead, nose, and upper lip. It primarily affects the skin's pigment-producing cells, leading to increased melanin production. This condition is more common in women, particularly during pregnancy or with the use of hormonal contraceptives. The patches are usually symmetrical and can vary in size and shape. Although melasma does not cause physical pain or harm, it can affect a person's appearance and self-esteem. Sun exposure often worsens the discoloration, making it more noticeable. The condition involves the skin system and mainly impacts cosmetic appearance.
Clinical Definition
Melasma (chloasma) is a chronic acquired disorder characterized by hypermelanosis of the facial skin due to increased melanin production by epidermal and/or dermal melanocytes. It is commonly triggered by ultraviolet radiation, hormonal influences such as pregnancy or oral contraceptives, and genetic predisposition. The hallmark clinical feature is the presence of symmetrical, irregularly shaped, hyperpigmented macules and patches predominantly on sun-exposed areas of the face. The pathogenesis involves melanocyte hyperactivity without an increase in melanocyte number, often exacerbated by estrogen and progesterone. Melasma is significant due to its chronicity and cosmetic impact, often requiring long-term management. Histologically, increased melanin is seen in the basal and suprabasal layers of the epidermis, sometimes with dermal melanophages.