Pigmentation disorders

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Melanocyt

Pigmentation disorders are diseases associated with an excess or lack of melanin, or the presence of another endogenous or exogenous pigment.[1]

Hyperpigmentation[edit | edit source]

Hyperpigmentation is an excess of melanin.

  • Ephelides, freckles – are sharply demarcated, yellowish or brown spots several mm in size. Rarely, they can also appear on the lips and oral cavity. It belongs to dominantly inherited deviations
  • Peutz-Jeghers syndrome – is an AD hereditary disease. It is manifested by intestinal polyposis and freckle-like pigmentation around the mouth and on the red lip.
  • Chloasma uterinum (melasma) are large, sharply defined, yellowish to yellowish-brown spots. They appear symmetrically on the temples and faces of girls and women. occurrence is determined by hormones, they often appear during pregnancy.
  • Poikilodermia Civatte is hyperpigmentation associated with telangiectasias. It occurs in middle-aged women on the lateral surfaces of the neck, probably after photodynamically acting substances.

Secondary hyperpigmentation[edit | edit source]

Removal - various bleaching agents (unreliable) - hydrargium amidochloratum, hydrogen peroxide, ...

Hypopigmentation[edit | edit source]

Hypopigmentation is a lack of melanin.

  • Leucoderma is secondary depigmentation at the site of healed skin disease manifestations. It usually retains the shape of the original efflorescences;
    • lleukoderma psoriaticum, syphiliticum, …
  • Albinism is an AR hereditary disorder of the tyrosinase enzyme metabolism associated with a total or partial absence of melanin.
Searchtool right.svg For more information see Albinism.
  • Vitiligo s a progressive chronic disease of unknown cause. It affects more women. Occurrence is often familial. It manifests itself as sharply defined white spots of various sizes, the edges of which have a "fan-like" hyperpigmentation. Hair may be bleached.
Searchtool right.svg For more information see Vitiligo.

Dyschromia[edit | edit source]

Dyschromia is hyperpigmentation caused by pigments other than melanin.

  • Hemosiderin pigmentation - hemosiderosis (capillaritis) is most often on the lower legs in varicose veins. It is a disease of unknown etiology manifested by itching, eczema and petechiae.
  • Bile dyes - manifested as jaundice.
Searchtool right.svg For more information see Icterus.
  • Exogenously - argyrosis is a gray discoloration of mucous membranes after treatment with silver solutions. It first appears on the gingiva. Exogenous dyschromia also includes tattoos.
Searchtool right.svg For more information see Dyschromia.


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Source[edit | edit source]

Reference[edit | edit source]

  1. PIZINGER, Karel. Dermatovenerologie. 1. edition. Plzeň : Euroverlag, 2012. ISBN 978-80-7177-985-8.