VITILIGO

VITILIGO - Gary J. Silko, MD, MS
BASICS
DESCRIPTION
• An acquired, slowly progressive depigmenting condition in small or large areas of the skin due to the disappearance of previously active melanocytes
- Focal (including segmental) vitiligo: 1 to a few scattered macules, occasionally in a dermatomal distribution
- Generalized vitiligo: Many widespread macules (most common form)
- Universal vitiligo: Little remaining normal pigment
- Acrofacial: Affects distal fingers and facial orifices
• System(s) Affected: Skin/Exocrine
• Synonym(s): Hypomelanosis; Depigmentation
ALERT
Pediatric Considerations
Childhood vitiligo is a distinct subset of vitiligo. Higher incidence of focal vitiligo. Also higher incidence of autoimmune and endocrine disease. Response is poor to topical psoralen plus ultraviolet exposure (PUVA) therapy, but can be tried. Topical steroids may be prescribed (e.g., desonide 0.05% cream every day for 4 months).
Pregnancy Considerations
Treatment with topical or oral psoralens is contraindicated.
GENERAL PREVENTION
While undergoing all therapies, avoid excessive sun exposure.
EPIDEMIOLOGY
• Predominant age: All ages: 50% begin before age 20 years.
• Predominant sex: Male = Female
Incidence
In the US: 500-1,000/100,000
RISK FACTORS
• Positive family history
• Autoimmune disorders including hemolytic anemia and adrenal insufficiency
• Major life crisis or illness
Genetics
Autosomal dominant with variable expression and incomplete penetrance. Positive family history in 30% of cases
ETIOLOGY
Etiology unclear, but thought to be an autoimmune reaction to preexisting melanocytes
ASSOCIATED CONDITIONS
• Addison disease
• Alopecia areata
• Chronic mucocutaneous candidiasis
• Diabetes mellitus (insulin dependent)
• Hypoparathyroidism
• Melanoma
• Pernicious anemia
• Polyglandular autoimmune syndrome
• Thyroid disorders (hyperthyroidism and hypothyroidism), 30% of patients with vitiligo
• Uveitis
• Halo nevi


DIAGNOSIS
SIGNS AND SYMPTOMS
• Loss of pigment
• Locally increased sunburning
• Predilection for acral areas and around orifices such as eyes, mouth, anus
• Pruritus (10%)
• Premature graying (35%)
• Koebner phenomenon (aggravation by trauma)
TESTS
Lab
• Routine blood and urine studies are usually normal in the absence of associated diseases in adults.
• In children, screen for autoimmune diseases with thyroid-stimulating hormone, CBC, and fasting glucose.
Diagnostic Procedures/Surgery
• Examination under Wood light accentuates the hypopigmented areas, especially in light-skinned individuals.
• Skin scraping and a potassium hydroxide (KOH) preparation can be examined microscopically to rule out tinea versicolor.
Pathological Findings
Complete absence of melanocytes in skin biopsy. At the margins one may see a few lymphocytes and large melanocytes with abnormal melanosomes.
DIFFERENTIAL DIAGNOSIS
Any condition that causes acquired hypomelanosis
• Tinea versicolor
• Leprosy
• Lupus erythematosus
• Pityriasis alba
• Atopic dermatitis
• Albinism
• Alopecia areata
• Chemical exposure (phenols, arsenic, chloroquine, hydroquinone)
• Steroid exposure
• Retinoic acid use
• Tuberous sclerosis
• Neurofibromatosis
• Melanocytic nevi (halo nevi)
• Tumor regression of malignant melanoma
• Piebaldism
• Hypopituitarism
• Hyperthyroidism
• Morphea
• Lichen sclerosis
TREATMENT
GENERAL MEASURES
• Appropriate health care: Outpatient except in rare cases of surgical skin grafting or transplantation
• Sun exposure can accentuate the difference between normal and abnormal skin, so for cosmetic reasons patients may wish to avoid this.
• Skin dyes and cosmetics may be used as cover-ups.
Diet
No special diet
Activity
Full activity
MEDICATION (DRUGS)
First Line
• Focal or segmental vitiligo
- A midpotency steroid cream can be applied daily for 3-4 months. If no response, advance to high-potency steroids. Clobetasol (Temovate) cream applied daily for 2 months (every other day on the face). Treatment may be resumed following a 1-4-month respite.
- Phototherapy with narrow band UVB 2 times per week. (1)[C]
• Generalized vitiligo:
- Oral systemic steroids, e.g., betamethasone 5 mg given 2 days in a row, then held the remainder of the week. This pattern continued for 2-4 months minimizes side effects and is effective in arresting the disease in many patients.
- Narrow-band UVB therapy is the preferred initial phototherapy, given 2 times per week.
- Oral trimethylpsoralen or methoxsalen (Oxsoralen-Ultra, 8-MOP) and UVA over a 12-24-month period
- Alternatively, depigmenting the remaining normal skin with monobenzone, a hydroquinone derivative, 20% cream may be elected. It should be applied b.i.d. for 3-6 months. (1)[C]
• Contraindications
- Absolute contraindications to use of psoralen compounds: Idiosyncratic reaction to psoralens, photosensitive disease (e.g., systemic lupus erythematosus, albinism, porphyria), invasive squamous cell carcinoma, melanoma, aphakia
- Relative contraindications to use of psoralen compounds: Cardiac disease, hepatic dysfunction, multiple basal cell carcinomas, prior radiation therapy, prior arsenic therapy
• Precautions
- Watch for skin atrophy and telangiectasias when using topical steroids, especially on the face.
- Watch for photosensitizers with UVA treatment.
- Severe burns possible with topical psoralens. Partially avoided with: 1:10 or 1:50 dilution of psoralens
- PUVA cannot be used for children 12 years of age due to immaturity of the ocular lens.
- Patients undergoing PUVA therapy should have a screening ophthalmologic examination to rule out subclinical retinal pigmentary disease, which is frequently associated with vitiligo.
• Significant possible interactions: Other photosensitizers, e.g., tetracyclines and retinoic acid
Second Line
• Patients with unresponsive focal vitiligo may be candidates for minigrafting with or without PUVA therapy.
• Levamisole 150 mg 2 days a week for several months has been effective in patients with limited or slowly spreading disease.
FOLLOW-UP
DISPOSITION
Issues for Referral
Dermatology consultation should be considered for facial or widespread vitiligo or when PUVA therapy may be necessary.
PROGNOSIS
• Only 5% repigment spontaneously.
• Best results are with PUVA therapy, with which 70% have repigmentation of head and neck area, less in other body areas. Lower percentages respond to topical therapy.
• There is no response in at least 20% of cases, especially long-standing cases.
• Once repigmentation occurs, it usually persists.
COMPLICATIONS
• Phototoxic reactions ranging from mild to severe with PUVA
• Skin atrophy and telangiectasias with topical steroids
• Contact dermatitis can occur with use of depigmenting agents and cosmetic covers.
PATIENT MONITORING
• With PUVA therapy, complete blood count, liver, renal function tests, and an antinuclear antibody should be done every 6 months.
• With topical steroids, follow at monthly intervals to avoid steroid-atrophy of the skin.
REFERENCES
1. James WD, Berger TG, Elston DM. Andrews' Diseases of the Skin. 10th ed. Philadephia, PA: WB Saunders; 2006: 860-863.
2. Freedberg IM, et al. Fitzpatrick's Dermatology in General Medicine, 6th ed. New York, NY: McGraw-Hill; 2003: 839-847.
3. Habif TP. Clinical Dermatology. 4th ed. New York, NY: Mosby; 2004.
MISCELLANEOUS
See also: Hyperthyroidism; Hypothyroidism, Adult; Pityriasis Alba; Tinea Versicolor