Vitiligo /ˌvɪtɨˈlaɪɡoʊ/ is a condition that causes depigmentation of
parts of the skin. It occurs when melanocytes,
the cells responsible for skin
pigmentation, die or are unable to function. The cause of vitiligo is
unknown, but research suggests that it may arise from autoimmune,
genetic, oxidative stress, neural, or viral causes.[1] The
incidence worldwide is less than 1%.[2] The
most common form is non-segmental vitiligo, which tends to appear in symmetric
patches, sometimes over large areas of the body.
Vitiligo on darker skin
The most notable symptom of vitiligo is depigmentation of
patches of skin that occurs on the extremities.[3][4] Although
patches are initially small, they often enlarge and change shape.[1][3] When
skin lesions occur,
they are most prominent on the face, hands and wrists.[3][4] Depigmentation
is particularly noticeable around body orifices, such as the mouth, eyes, nostrils, genitalia and umbilicus.[3][4]Some
lesions have hyperpigmentation around the edges.[5] Patients
who are stigmatised for their condition may experience
depression and similar mood disorders.[6] A
Black light (also referred to as a UVA light, Wood's lamp, or simply
ultraviolet light) can be used in the early phase of this disease for
identification and to determine effectiveness of treatment. Skin with vitiligo,
when exposed to a black light, will glow yellow, green or blue, in contrast to
healthy skin which will have no reaction.
Cause[edit]
Non-segmental[edit]
In non-segmental vitiligo (NSV), there is usually some form
of symmetry in
the location of the patches of depigmentation. New patches also appear over
time and can be generalized over large portions of the body or localized to a
particular area. Vitiligo where little pigmented skin remains is referred to as vitiligo
universalis. NSV can come about at any age (unlike segmental vitiligo, which is
far more prevalent in teenage years).[5]
Classes of non-segmental vitiligo include:
Generalized Vitiligo: the most common pattern, wide and
randomly distributed areas of depigmentation[7]
Universal Vitiligo: depigmentation encompasses most of the
body[7]
Focal Vitiligo: one or a few scattered macules in one area,
most common in children[7]
Acrofacial Vitiligo: fingers and periorificial areas[7]
Mucosal Vitiligo: depigmentation of only the mucous
membranes[7]
Segmental[edit]
Segmental vitiligo (SV) differs in appearance, etiology and
prevalence from associated illnesses. Its treatment is different from that of
NSV. It tends to affect areas of skin that are associated with dorsal roots
from the spine and is most often unilateral. It spreads much more rapidly than
NSV and, without treatment, it is much more stable/ static in course and is not
associated with auto-immune diseases. It is a very treatable condition that
responds to topical treatment.[5]
