Common Disorders of Skin Pigmentation

Vitiligo:

  • -It is an autoimmune disease causing focal destruction of melanocytes in the skin
  • -It affects 0.5 to 1% of the population
  • -it causes insidious loss of skin color in patches
  • -it can affect the hair
  • -It should be differentiated from other conditions that cause skin loss of pigmentation:
  • Tines Versicolor (fungal infection)
  • Pityriasis alba
  • Idiopathic Guttate Hypomelanosis
  • Treatment of Vitiligo:
  • High potency Steroids cream
  • Topical immunomodulator
  • UV light
  • Depigmentation therapy
Idiopathic Guttate Hypomelanosis

Idiopathic Guttate Hypomelanosis

Pityriasis Alba

Tinea Versicolor

Melasma

-It is also called the mask of pregnancy

-Melanocytes overproduce Melanin due to:

  • Ultraviolet radiation (sun)
  • Genetic predisposition
  • Hormones (pregnancy and birth control pills)

-Women with darker skin are usually affected

-It presents with tan colored or darker skin on sun exposed face

-The tan can fade away after the inciting factor is resolved (for example after delivery in pregnant patients but resolution will take months to years.

-Treatment:

  • Strict sun protection
  • Avoidance of causative factors
  • Skin bleaching agent- Hydroquinone
  • Chemical peels
  • Laser

Post inflammatory Hyperpigmentation

  • It causes hyperpigmented spots at the site of previous skin inflammation or infection, it is more common in blacks