Acquired circumscribed depigmentation.
6.3.4 Vitiligo
Definition
Aetiology & Pathogenesis
Autoimmune process affecting, finally leading to destruction of melanocytes. Association with atopy, autoimmune thyroid disease.
Signs & Symptoms
Circumscribed small (confetti-like) macules which may also be confluent to produce larger patches, usually symmetrical; complete depigmentation under Wood’s light. Not itchy.
Localisation
Favours face, hands, ano-genital region, peri-umbilical area, but any location possible. Sometimes generalized. May affect hair (poliosis).
Classification
Segmental (affecting only one side of the body).
Non-segmental (affects both sides of the body). Acral and central type.
Laboratory & other workups
Screen for other autoimunne disseases, if appropriate.
Dermatopathology
Absent epidermal pigment, lymphocytic inflammatory infiltrate in early phase, destruction of melanocytes in later chronic phase.
Course
Spontaneous resolution possible. Acral sites (hands, feet and ano-genital areas) are often resistant to treatment; facial vitiligo is often more responsive to treatment than other body sites. Treatment response generally declines with the age of the lesion.
Complications
Because of lack of biological filter (melanin pigment) increased risk of sunburn, and consequent actinic damage. Often severe dysmorphophobia.
Diagnosis
Clinical findings.
Differential diagnosis
Albinism, pityriasis versicolor, naevus anaemicus, naevus depigmentosus, pityriasis alba, dry skin in darker skin types, hypomelanosis pigmentosa, macular form of lichen sclerosus, any cause of post-inflammatory hypopigmentation, other rare, hereditary causes of hypopigmentation (e.g. piebaldism etc.).
Prevention & Therapy
Early treatment.
Topical potent/superpotent corticosteroids; topical calcineurin inhibitors; phototherapy; consider melanocyte-keratinocyte transplants from normally pigmented skin. Consider afamelanotide with UVB photo(chemo)therapy.Cosmetic camouflage with make-up. Bleaching agents for normally pigmented skin if vitiligo widespread.
Topical sunscreens to prevent sun damage.
Counselling/psychological support especially for those with darker skin types, where the psychosocial impact may be severe.
Differential Diagnosis
Podcasts
Tests
- Statement 1 It is always important to check the perianal region when considering the diagnosis of vitiligo
- Which of these treatment approaches is not indicated for vitiligo?
- Statement 1 Vitiligo is characterized by focal depigmentation.
- Which of these factors DO NOT trigger vitiligo?
- Which if these skin changes is not associated with vitiligo?
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