Dyspigmentation

Dyspigmentation is a term used to describe abnormal coloration of the skin resulting from changes in melanin production, distribution, or removal. It is not a single disease but a feature of many conditions that affect the pigmentary system. Dyspigmentation can be categorized as hyperpigmentation, in which there is excess pigment, or hypopigmentation, in which pigment is reduced or lost.

Hyperpigmentation examples include melasma, post-inflammatory hyperpigmentation, lentigines (age spots), and freckles. Hypopigmentation examples include vitiligo, albinism, and pityriasis versicolor with hypopigmented patches. Other pigmentary changes may occur with inflammatory skin conditions, infections, or drug reactions.

Causes and risk factors include ultraviolet radiation exposure, hormonal influences (such as pregnancy or certain medications), aging, inflammatory or traumatic skin injury, and medication effects (for example, some antibiotics, antimalarials, or chemotherapeutic agents). Genetic predisposition and skin type also influence the likelihood and appearance of dyspigmentation.

Diagnosis is typically clinical, based on history and examination. Wood’s lamp testing and dermoscopy can aid evaluation, and a biopsy may be used in uncertain cases to distinguish pigmentary disorders.

Treatment aims to address the underlying cause when possible and to reduce cosmetic impact. Common topical therapies for hyperpigmentation include hydroquinone, azelaic acid, kojic acid, vitamin C, and retinoids, often combined with sunscreen. Procedures such as chemical peels and laser therapies may be considered for selected cases under specialist care. For hypopigmentation disorders like vitiligo, treatment may include topical steroids or calcineurin inhibitors and phototherapy. Prevention centers on sun protection and early treatment of inflammatory skin conditions.

Prognosis varies by condition; some pigmentary changes improve over time, others persist, and the psychosocial impact may be significant.