Disorders of Pigmentation
(Hypopigmentation and Hyperpigmentation)

Too little (hypopigmentation) or too much (hyperpigmentation) pigment ("coloring") of the skin, especially if localized and obviously noticeable from the remainder of the patient's skin, may cause anxiety or feelings of inferiority and self-consciousness in patients. Cosmetic applications or therapies may improve these conditions but almost all of them are chronic in nature.

Hyperpigmentation disorders may be localized (freckles, lentigos, melasma, post-inflammatory hyperpigmentation) or generalized due to systemic diseases or ingestion of certain compounds.

Hypopigmentation disorders include post-inflammatory hypopigmentation, hypopigmentation due to localized therapies (liquid nitrogen, biopsies), pityriasis alba, or vitiligo. Vitiligo affects up to 2 % of the population. Melanocytes are completely absent in depigmented areas in vitiligo.