Pigmentary Diseases PowerPoint Presentation PDF

DISORDERS OF PIGMENTATION Dr. Sarah Raed Assistant Lecturer of Dermatology, Duhok.College of Medicine FITZPATRICK SKIN TYPES CLASSIFICATION SOME CAUSES OF HYPOPIGMENTATION  OCULOCUTANEOUS ALBINISM  Autosomal recessively inherited.  There is a normal number of melan...

DISORDERS OF PIGMENTATION Dr. Sarah Raed Assistant Lecturer of Dermatology, Duhok.College of Medicine FITZPATRICK SKIN TYPES CLASSIFICATION SOME CAUSES OF HYPOPIGMENTATION  OCULOCUTANEOUS ALBINISM  Autosomal recessively inherited.  There is a normal number of melanocytes in the basal layer of the epidermis, but lack tyrosinase and are unable to synthesize melanin.  The whole skin is white and pigment is also lacking in the hair, iris and retina.  Albinos have poor sight, photophobia and a nystagmus.  Sunburn is common on unprotected skin.  MANAGEMENT  Albino patients must learn to protect themselves against UVR with sunscreens.  Avoidance of sun wherever possible.  Regular checking to detect early changes of skin cancer is also important.  PIEBALDISM  Autosomal dominant.  Due to absence of melanocytes in the affected skin and hair follicles.  In this condition, there is a white forelock and white patches on the skin surface PEIBALDISM  VITILIGO  Its an acquired, idiopathic disorder characterized by circumscribed Depigmented macules and patches  Functional melanocytes disappear from involved skin by a mechanism(s) that has not yet been identified.  EPIDEMIOLOGY  Vitiligo occurs in 1–2% of the population.  The disease affects both sexes equally.  It may start at any age but usually affects children and young adults. It started before the age of 20 in 50% of the cases.  PATHOGENESIS  Multifactorial  Genetic background is evident by presence of 30-40 % positive family history of vitiligo.  The autoimmune hypothesis is the most acceptable theory.  Inflammatory infiltrate consist mainly of T- lymphocytes, some of them invade the epidermis and destroy the melanocytes.  CLINICAL FEATURES  Sharply defined areas of depigmentation appear.  The depigmented patches are often symmetrical, especially when they are over the limbs and face.  It is a serious cosmetic problem for darkly pigmented people.  The condition often starts in childhood and either spreads, ultimately causing total depigmentation, or persists, with irregular remissions and relapses.  Vitiligo could be Generalized or Localized SYSTEMIC ASSOCIATION Increased risk of Autoimmune diseases:  Thyroid dis. [Hashimoto’s, Grave’s]  Addison’s disease  Pernicious Anemia  Insulin dependent Diabetes  Alopecia Areata BAD PROGNOSTIC SIGNS:  Very early onset in childhood.  Lips and digits “Lip-tip vitiligo”  Leukotrichia “Grey hair in the affected area”.  Complete or universal type.  Segmental type.  Positive family history. WOOD’S LAMP  TREATMENT  Reassurance.  Topical corticosteroids.  Topical Immunomodulators such as tacrolimus, pimecrilamus.  Photo(chemo)therapy:Narrow Band UVB (NBUVB) , Psoralen plus UVA (PUVA)  TREATMENT  Excimer Laser  Sugrical :Minigrafting, Blister grafting, Cultured Autologous Melanocytes  Cosmetic camouflage.  Depigmentation : 20% monobenzyl ether of hydroquinone (MBEH) QUESTIONS ?