Vitiligo Flashcards
What is vitiligo?
A chronic, autoimmune skin disorder characterized by the progressive loss of melanocytes, leading to depigmented patches on the skin.
What is the hallmark feature of vitiligo?
Well-demarcated, depigmented (white) macules and patches on the skin.
At what age does vitiligo typically present?
It often starts in childhood or early adulthood, with 50% of cases presenting before age 20.
What causes vitiligo?
Autoimmune destruction of melanocytes, possibly triggered by genetic, environmental, or oxidative stress factors.
What immune cells are involved in vitiligo?
Cytotoxic T-cells and autoantibodies that target melanocytes.
What are some genetic associations with vitiligo?
Associated with HLA genes and polymorphisms in genes regulating immune responses, such as NLRP1 and PTPN22.
What are the key clinical features of vitiligo?
Depigmented macules and patches, often symmetric.
Lesions are more noticeable in sun-exposed areas and on darker skin.
Typically non-itchy and asymptomatic.
What are the common sites of vitiligo lesions?
Face (perioral, periocular).
Hands, feet, and joints.
Genitals.
Areas of trauma (Koebner phenomenon).
What is the Koebner phenomenon in vitiligo?
Depigmentation occurring at sites of skin trauma or injury.
What are the two main types of vitiligo?
Non-segmental vitiligo (NSV): Most common, with bilateral and symmetrical patches.
Segmental vitiligo (SV): Unilateral, limited to one dermatome, often earlier onset.
How does vitiligo affect hair and mucosa?
Hair: Can cause depigmentation (leukotrichia).
Mucosa: Commonly affects oral and genital mucosa.
What autoimmune diseases are associated with vitiligo?
Thyroid disorders (e.g., Hashimoto’s thyroiditis).
Type 1 diabetes.
Addison’s disease.
Pernicious anemia.
Alopecia areata.
How is vitiligo diagnosed?
Clinical examination based on characteristic depigmented patches.
Wood’s lamp examination: Depigmented areas fluoresce bright white.
Skin biopsy (rarely needed): Absence of melanocytes confirms diagnosis.
What are first-line treatments for vitiligo?
Topical corticosteroids: For localized, active disease.
Topical calcineurin inhibitors (e.g., tacrolimus, pimecrolimus): Safe for sensitive areas like the face and genitals.
How is widespread or refractory vitiligo treated?
Narrowband UVB (NB-UVB) phototherapy.
Psoralen and UVA (PUVA) therapy (less common).
Oral corticosteroids for rapidly progressing disease.
