Dyschromia of the skin is a persistent disruption of skin color. Dyschromia of the skin can be caused by: 1) a violation of the formation and deposition of pigment melanin: hyperpigmentation (see Freckles, Chloasma ) and depigmentation (see Vitiligo, Leukoderma); 2) the deposition of hemosiderin pigment in the skin (see hemosiderosis of the skin ) and 3) exogenous pigments (tattooing, impregnation). The causes of skin dyschromia are diverse: radiation damage, chemical, including drug intoxication , central nervous system diseases, endocrine system, chronic infections, hereditary anomalies, etc. Skin dyshromia can be diffuse (albinism, melasma) and limited (vitiligo, tattooing); primary (syphilitic leukoderma) and secondary - pigmentation or depigmentation after skin rashes. See also Pigmentation .