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
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
