Suggested to be a chronic autoimmune disease associated with other autoimmune processes such as pernicious anemia, rheumatoid arthritis, psoriasis, alopecia areata, type I diabetes, Addison’s disease, thyroid diseases, polyglandular autoimmune syndrome, inflammatory bowel disease, and lupus.

Results from loss of melanocytes.

An acquired pigmentary disorder characterized by hypopigmented macules.

About 1% of the population has vitiligo which causes painless distinct light-colored patches of the skin on the face, hands, and legs. 

Caused by autoimmune destruction of melanocytes.

Complex process that involves multile susceptibilty genes and unknown environmental factors.

The association with generalized vitiligo and autoimmune disease suggest shared genetic components.

The prognosis is a variable, and is affected by both environment and genetic factors.

In a genomewide association study of 579,146 single nucleotide polymorphisms in 1514 patients with generalized vitiligo of European descent: significant associations with generalized vitiligo and SNPs associated with other autoimmune diseases-PTPN22, LPP, ILRA, UBASH3A, RERE, and TYR.

The presence of TYR SNP appears to be mutually exclusive btween susceptibility to vitiligo and asuceptibility to melanoma.

Most common depigmenting disorder.

Prevalence worldwide is 0.5%.

Approximately 50% of patients present before the age of 20 years.

No gender difference and no racial or skin type differences.

Nonsegmental, or generalized disease, the most common form and accounts for 85-90% of cases.

Segmental form of the disease has an earlier onset, and may account for as much as 30% of childhood cases.

Both nonsegmental and segmental vitiligo can start out as focal abnormalities with small affected area of involvement of less than 15cm2.

Segmental and nonsegmental disease can rarely occur together.

When segmental and nonsegmental vitiligo occur together the segmental lesions are more difficult to treat.

Manifested as loss of epidermal melanocytes (Gauthier).

Completely depigmented areas have no inflammation.

At the margins of rapidly progressive depigmented disease, areas mononuclear cells may be present in nonsegmental lesions.

Cause of nonsegmental disease may involve immunologic factors, oxidative stress or sympathetic neurogenic disturbance.

In nonsegmental disease the upward migration of melanocytes 24 hours after mechanical trauma in perilesional areas indicates a cutaneous response to nonspecific trauma in the pathogenesis of the disease (Koebner‘s phenomenon).

In segmental disease a neurogenic sympathetic disturbance is suspected to contribute to the initiation of the process and a genetic anomaly may be related.

Interferon gamma producing and melanocyte killing skin resident T cells accumulate in depigmented lesions.

These pathogenic T cells have the capacity to maintain pathological features over a period of many years.

Populations in Europe related to autoimmune diathesis and some genes.

Autoimmune related disease associated with gene encoding NACHT leucine-rich repeat protein-1 or NALP1 has been identified (Jin Y).

In nonsegmental disease macules have homogenous depigmentation with well defined borders.

Loss of hair pigmentation may occur in advanced disease.

After sun exposure the interface between the hypopigmentated and normal areas may become hyperpigmented.

In rapidly progressive disease patchy depigmentation may follow pinpoint depigmentation (Taieb A).

In segmental disease lesions have more irregular borders and less homogenous depigmentation than in nonsegmental vitiligo.

In individuals with dark skin the mucosa may be prominently involved.

Halo nevi are 8-10 times more common in such patients than in the general population.

Halo nevi that are multiple may be associated with cellular autoimmunity against nevi cells and may indicate higher risk of vitiligo among patients with a family history.

Some patients with nonsegmental disease vitiligo an accelerated phase may occur over weeks to months.

Thyroid functions should be measured annually in nonsegmental vitiligo as there is an increased risk of autoimmune thyroid disease, especially Hashimoto’s disease.

Association with autoimmune disease varies with the patient’s skin type and race.

More than 40% have elevated anti-nuclear antibody levels, and almost half of the patients have elevated thyroid peroxidase antibodies.

Over 50% of the patients tested have low or insufficient levels of 25-OH vitamin D.

In patients with melanoma, vitiligo like symptoms can occur as immunotherapy adverse reaction between 3.4 and 25% of patients during treatment with an immune checkpoint inhibitor.

Phototherapy forces skin cells to manufacture melanin to protect the body from UV damage. 

Treatment cannot currently cure this disease. 

Corticosteroid topical,therapy works best for people who recently developed vitiligo.

When used short-term, this medication is often effective for both children and adults.

Tacrolimus ointment or pimecrolimus cream can be used for a longer time than corticosteroids. 

These work best to treat skin on the head or neck.

Calcipotriene can be effective when used with a corticosteroid. 

Light therapy exposes the skin to ultraviolet (UVB)  light that can restore natural skin color. 

Light therapy is most effective at restoring color to the face and neck, and the lips, tips of the fingers, and toes are least responsive to treatment with light therapy.

Two types of surgery are used to treat vitiligo:

Skin graft

Cell transplant: healthy pigmented skin cells are then placed into skin with vitiligo. 

Surgery usually is not recommended for people who have active vitiligo: if over the last 12 months new spots have developed or existing spots have grown.

Janus kinase inhibitor (JAK inhibitor for short) may be an effective treatment for vitiligo. 

JAK inhibitors decrease an overactive immune system, which can stop the body from destroying melanocytes, allowing the skin can re-pigment.

Maintenance therapy often required to keep treatment results.

The application of ruxolitinib cream resulted in greater re-pigmentation in vitiligo lesions than vehicle control through 52 weeks, but it is associated with acne and pruritus at the application site.

JAK  signaling pathway has a critical role in activating and polarizing Interferon gamma producing T cells, and is a viable target for the treatment of vitiligo with JAK inhibitors.

JAK inhibitors have a 30 to 50% treatment response rate.

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