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LeenaKoulu

Vitiligo

Vitiligo is an autoimmune disease characterised by slowly progressing patches of depigmented skin throughout the body.
Other autoimmune diseases occur in 10-15% of the patients. The most common are thyroid autoimmune diseases.
Treatment is most successful if it is started at an early stage of the disease.
Vitiligo patches tend to sunburn easily.

Vitiligo affects 0.5-2% of the population. Vitiligo is encountered in all races and equally between men and women.
Almost half of patients are under 20 years of age at disease onset.
According to different studies, 10-50% of patients also have close relatives with vitiligo or other autoimmune diseases.
The mode of inheritance for vitiligo is not known. Multiple susceptibility loci have been identified. Regulation disturbances affecting multiple genes are probable as is incomplete penetrance.
Vitiligo is an autoimmune disease in which cytotoxic CD8-positive T cells destroy epidermal melanocytes. The underlying precipitating factor is unknown.
Skin damage or sunburn may trigger vitiligo (Köbner phenomenon). Many patients connect the onset of vitiligo with pregnancy or mental stress.

Vitiligo patches (pictures 1 2 3) usually occur symmetrically in the limbs (pictures 4 5 6).
The typical sites on the trunk are the umbilical area and around the nipples. In the face depigmentation characteristically occurs around the mouth and eyes.
Light-coloured patches may also occur in the scalp hair or in hair on other areas of the body.
The patches usually progress gradually, and spontaneous repigmentation occurs only rarely.
Segmental vitiligo, which is unilateral linear or blotch-like, occurs more rarely. It develops quickly within 3-4 months and then ceases to progress.
Affected skin shows an almost complete absence of melanocytes.
The depigmented areas are prone to sunburn and must be protected with clothing or sunscreen with a SPF of at least 30.

An association may exist between vitiligo and other autoimmune disorders.
Laboratory tests in vitiligo
- Thyroid disease screening Examining a Patient with a Thyroid Complaint (thyroid abnormalities are present in about 20% of cases, but the symptom onset does not usually coincide with that of vitiligo)
  - TSH, free T4
  - TPO antibodies and antithyroglobulin antibodies. These identify patients who have an increased risk of developing autoimmune thyroiditis.
- As required: basic blood count with platelets, antinuclear antibodies, fasting blood glucose.

Diagnosis is made on the basis of clinical findings. If necessary, histopathological testing may be used to confirm diagnosis.
The skin lesions in pityriasis versicolor Pityriasis Versicolor are pale in the summer and may be confused with vitiligo. Pityriasis versicolor lesions are associated with slight scaling which is not a feature in vitiligo.
Lichen sclerosus of the vulva or penis Lichen Sclerosus may resemble vitiligo. A biopsy will assist in diagnosis.

No definitely effective treatment is available.
In segmental vitiligo the treatment result is especially poor.
It may be decided, in agreement with the patient, not to attempt to treat vitiligo.
In light skinned patients, the patches are hardly noticeable during the winter months.
Many patients are content if the most visible lesions can be camouflaged with specially chosen make-up or self-tanning cosmetic products.
The patient must protect his/her skin against the sun as vitiligo patches are prone to sunburn, and if unaffected skin areas become suntanned the patchiness of the skin will be emphasised.
The possible treatment of vitiligo is the responsibility of a dermatologist.
- Potent glucocorticoid creams may be used for vitiligo that is limited to a small area on the trunk or limbs, once daily for a maximum of 3 months or in 2-week periods with 2-week pauses in between for a maximum of 6 months. Patients should be monitored for potential dermatological adverse effects of glucocorticoids.
- Tacrolimus is the first-line topical therapy in facial vitiligo. Long-term treatment and maintenance treatment are possible.
- Narrowband UVB phototherapy may be used when vitiligo covers > 5-10% of the surface area of the skin.
- The treatment response is best in young patients with vitiligo that has appeared recently. The response is usually worst on limbs.
- New therapies, such as Janus kinase (JAK) inhibitors, are under development.

Vitiligo impairs the patient's quality of life to the same degree as psoriasis, atopic dermatitis or hand dermatitis.
In some cultures vitiligo is considered particularly traumatic. A historical/cultural explanation can probably be found in the differential diagnosis: leprosy and late stage syphilis are also associated with white patches.
A specialized care unit can be consulted regarding treatment options for vitiligo, if needed.
At least in specialist care, the management protocol should include the use of a quality of life questionnaire specific to the patient's condition (DLQI = Dermatology Life Quality Index http://www.dermatology.org.uk/downloads/dlqifinnish.pdf).

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Rodrigues M, Ezzedine K, Hamzavi I ym. New discoveries in the pathogenesis and classification of vitiligo. J Am Acad Dermatol 2017;77(1):1-13. [PubMed]
Rodrigues M, Ezzedine K, Hamzavi I ym. Current and emerging treatments for vitiligo. J Am Acad Dermatol 2017;77(1):17-29. [PubMed]
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