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Vitiligo | Ricardo Side

Wednesday, October 24, 2012


Background
Vitiligo is an acquired pigmentary disorder of the skin and mucous membranes, and it is characterized by circumscribed depigmented macules and patches. Vitiligo is a progressive disorder in which some or all of the melanocytes in the affected skin are selectively destroyed. Vitiligo affects 0.5-2% of the world population, and the average age of onset is 20 years.
Pathophysiology
Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis. It is related to both genetic and nongenetic factors. Although several theories have been proposed about the pathogenesis of vitiligo, the precise cause remains unknown. Generally agreed upon principles are an absence of functional melanocytes in vitiligo skin and a loss of histochemically recognized melanocytes, owing to their destruction. However, the destruction is most likely a slow process resulting in a progressive decrease of melanocytes. Theories regarding destruction of melanocytes include autoimmune mechanisms,[1] cytotoxic mechanisms, an intrinsic defect of melanocytes, oxidant-antioxidant mechanisms, and neural mechanisms.
Autoimmune destruction of melanocytes
The autoimmune theory proposes alteration in humoral and cellular immunity in the destruction of melanocytes of vitiligo. Thyroid disorders, particularly Hashimoto thyroiditis and Graves disease; other endocrinopathies, such as Addison disease and diabetes mellitus; and alopecia areata; pernicious anemia; inflammatory bowel disease; psoriasis; and autoimmune polyglandular syndrome are all associated with vitiligo.
The most convincing evidence of an autoimmune pathogenesis is the presence of circulating antibodies in patients with vitiligo.[2] The role of humoral immunity is further supported by the observation that melanocytes are destroyed in healthy skin engrafted onto nude mice injected with vitiligo patient sera.[3]
In addition to the involvement of humoral immune mechanisms in the pathogenesis of vitiligo, strong evidence indicates involvement of cellular immunity in vitiligo. Destruction of melanocytes may be directly mediated by autoreactive CD8+ T cells. Activated CD8+ T cells have been demonstrated in perilesional vitiligo skin. In addition, melanocyte-specific T cells have been detected in peripheral blood of patients with autoimmune vitiligo.[4]
Intrinsic defect of melanocytes
Vitiligo melanocytes may have an intrinsic defect leading to melanocyte death. These melanocytes demonstrate various abnormalities, including abnormal, rough endoplasmic reticulum and incompetent synthesis and processing of melanocytes. In addition, homing-receptor dysregulation has also been detected. Early apoptosis of melanocytes has also been suggested as a cause of reduced melanocyte survival; however, subsequent investigation found that the relative apoptosis susceptibility of vitiligo melanocytes was comparable with that of normal control pigment cells.[5]
Disturbance in oxidant-antioxidant system in vitiligo
Oxidant stress may also play an essential role in the pathogenesis of vitiligo. Studies suggest that accumulation of free radicals toxic to melanocytes leads to their destruction. Because patients with vitiligo exhibit a characteristic yellow/green or bluish fluorescence in clinically affected skin, this led to the discovery that the fluorescence is due to accumulation of 2 different oxidized pteridines. The overproduction of pteridines led to the discovery of a metabolic defect in tetrahydrobiopterin homeostasis in patients with vitiligo, which results in the accumulation of melanocytotoxic hydrogen peroxide.[6]
Because oxidative stress has been suggested to be the initial pathogenic event in melanocyte degeneration, several studies have been conducted to evaluate this theory. Recent investigations set out to evaluate the role of oxidative stress by measuring levels of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in lesional and normal skin of patients with vitiligo and in the skin of normal control subjects. They concluded oxidative stress is increased in vitiligo, as indicated by high levels of SOD and low levels of CAT in the skin of vitiligo patients.[7]
Neural theory
Case reports describe patients afflicted with a nerve injury who also have vitiligo have hypopigmentation or depigmentation in denervated areas. Additionally, segmental vitiligo frequently occurs in a dermatomal pattern, which suggests that certain chemical mediators are released from nerve endings that affect melanin production. Further, sweating and vasoconstriction are increased in depigmented patches of vitiligo, implying an increase in adrenergic activity. Finally, increased urinary excretion of homovanillic acid and vanilmandelic acid (neurometabolites) has been documented in patients with vitiligo. This may be a secondary or primary phenomenon.[8]
In summary, although the ultimate cause of vitiligo is not completely known, this condition does not reflect simple melanocyte loss, but possible immunologic alterations and other molecular defects leading to pigment cell destruction; however, melanocytes may be present in depigmented skin after years of onset and may still respond to medical therapy under appropriate stimulation.
Genetics of vitiligo
Vitiligo is characterized by incomplete penetrance, multiple susceptibility loci, and genetic heterogeneity.[9] The inheritance of vitiligo may involve genes associated with the biosynthesis of melanin, a response to oxidative stress, and regulation of autoimmunity.[10]
Human leukocyte antigens (HLAs) may be associated, but not in a consistent manner. For example, HLA-DR4 is increased in blacks, HLA-B13 is increased in Moroccan Jews, and HLA-B35 is increased in Yemenite Jews. An association with HLA-B13 is described in the presence of antithyroid antibodies.
A genome-wide association study of generalized vitiligo in an isolated European founder population identified that the group had significant association with single-nucleotide polymorphisms in a 30-kb LD block on band 6q27, in close vicinity to IDDM8, which is a linkage and an association signal for type I diabetes mellitus and rheumatoid arthritis. Only one gene, SMOC2, is in the region of association, within which SNP rs13208776 attained genome-wide significance for association with other autoimmune diseases and vitiligo.[11]
The age of onset has a genetic component; in another genomewide association study, a quantitative locus for age of onset was found in the major histocompatibility complex class II region near a region associated with generalized vitiligo susceptibility.[12]
Epidemiology
Frequency
United States
In the United States, the relative rate of vitiligo is 1%.
International
Vitiligo is relatively common, with a rate of 1-2%. Approximately 30% of vitiligo cases occur with a familial clustering of cases.
Sex
A female preponderance has been reported for vitiligo, but it is not statistically significant and the discrepancy has been attributed to an increase in reporting of cosmetic concerns by female patients.
Age
Vitiligo may appear at any time from birth to senescence, although the onset is most commonly observed in persons aged 10-30 years.
Vitiligo rarely is seen in infancy or old age. Nearly all cases of vitiligo are acquired relatively early in life.
The average age of onset for vitiligo is approximately 20 years. The age of onset is unlikely to vary between the sexes.
Heightened concern about the appearance of the skin may contribute to an early awareness of vitiligo among females.
History
The most common form of vitiligo is an amelanotic macule or patch surrounded by healthy skin. The macules are chalk or milk-white in color, and lesions are well demarcated.
The lesions are not readily apparent in lightly pigmented individuals; however, they are easily distinguishable with a Wood lamp examination.
Physical
Vitiligo manifests as acquired white or hypopigmented macules or patches. The lesions are usually well demarcated, and they are round, oval, or linear in shape. The borders may be convex.[6] Lesions enlarge centrifugally over time at an unpredictable rate. Lesions range from millimeters to centimeters in size. Initial lesions occur most frequently on the hands, forearms, feet, and face, favoring a perioral and periocular distribution.
Vitiligo lesions may be localized or generalized, with the latter being more common than the former. Localized vitiligo is restricted to one general area with a segmental or quasidermatomal distribution. Generalized vitiligo implies more than one general area of involvement. In this situation, the macules are usually found on both sides of the trunk, either symmetrically or asymmetrically arrayed.
The most common sites of vitiligo involvement are the face, neck, and scalp. Many of the most common sites of occurrence are areas subjected to repeated trauma, including the following:
  • Bony prominences
  • Extensor forearm
  • Ventral wrists
  • Dorsal hands
  • Digital phalanges
Involvement of the mucous membranes is frequently observed in the setting of generalized vitiligo. Vitiligo often occurs around body orifices such as the lips, genitals, gingiva, areolas, and nipples.
Body hair (leukotrichia) in vitiliginous macules may be depigmented. Vitiligo of the scalp usually appears as a localized patch of white or gray hair, but total depigmentation of all scalp hair may occur. Scalp involvement is the most frequent, followed by involvement of the eyebrows, pubic hair, and axillary hair, respectively. Leukotrichia may indicate a poor prognosis in regard to repigmentation. Spontaneous repigmentation of depigmented hair in vitiligo does not occur.
Clinical Variants
Trichrome vitiligo has an intermediate zone of hypochromia located between the achromic center and the peripheral unaffected skin. The natural evolution of the hypopigmented areas is progression to full depigmentation. This results in 3 shades of color—brown, tan, and white—in the same patient, as in the image below.
Description: Trichrome vitiligo. Trichrome vitiligo.
Marginal inflammatory vitiligo results in a red, raised border, which is present from the onset of vitiligo (in rare cases) or which may appear several months or years after the initial onset. A mild pruritus may be present, as in the image below.
Description: Marginal inflammatory vitiligo. Marginal inflammatory vitiligo.
Quadrichrome vitiligo is another variant of vitiligo, which reflects the presence of a fourth color (ie, dark brown) at sites of perifollicular repigmentation. A case of pentachrome vitiligo with 5 shades of color has also been described.[8]
Blue vitiligo results in blue coloration of vitiligo macules. This type has been observed in a patient with postinflammatory hyperpigmentation who then developed vitiligo.
Koebner phenomenon is defined as the development of vitiligo in sites of specific trauma, such as a cut, burn, or abrasion. Minimum injury is required for Koebner phenomenon to occur.
Clinical Classifications of Vitiligo
The classification system is important because of the special significance assigned by some authorities to each type of vitiligo. The most widely used classification of vitiligo is localized, generalized, and universal types and is based on the distribution, as follows:
Localized vitiligo
  • Focal: This type is characterized by one or more macules in one area, most commonly in the distribution of the trigeminal nerve.
  • Segmental: This type manifests as one or more macules in a dermatomal or quasidermatomal pattern. It occurs most commonly in children. More than half the patients with segmental vitiligo have patches of white hair or poliosis. This type of vitiligo is not associated with thyroid or other autoimmune disorders.
  • Mucosal: Mucous membranes alone are affected.
Generalized vitiligo
  • Acrofacial: Depigmentation occurs on the distal fingers and periorificial areas.
  • Vulgaris: This is characterized by scattered patches that are widely distributed.
  • Mixed: Acrofacial and vulgaris vitiligo occur in combination, or segmental and acrofacial vitiligo and/or vulgaris involvement are noted in combination.
Universal vitiligo
This is complete or nearly complete depigmentation. It is often associated with multiple endocrinopathy syndrome.
Classification of Vitiligo by Progression, Prognosis, and Treatment
When progression, prognosis, and treatment are considered, vitiligo can be classified into 2 major clinical types: segmental and nonsegmental, as demonstrated in the images below.
Segmental
This usually has an onset early in life and rapidly spreads in the affected area. The course of segmental vitiligo can arrest, and depigmented patches can persist unchanged for the life of the patient.
Nonsegmental
This type includes all types of vitiligo, except segmental vitiligo.[13] See the images below.
Description: Segmental vitiligo. Segmental vitiligo. Description: Nonsegmental vitiligo. Nonsegmental vitiligo.
A single-center study of 213 patients aged 17 years or younger with segmental or nonsegmental vitiligo found that nonsegmental vitiligo was more strongly linked than segmental vitiligo to markers of autoimmunity or inflammation such as halo naevi and thyroid antibodies; patients with nonsegmental vitiligo were also more likely to have a family history of vitiligo or autoimmunity.[14]
Causes
Theories regarding destruction of melanocytes include autoimmune mechanisms, cytotoxic mechanisms, intrinsic melanocyte defects, oxidant-antioxidant mechanisms, and neural mechanisms.
  • Autoimmune and cytotoxic hypotheses: Aberration of immune surveillance results in melanocyte dysfunction or destruction.
  • Neural hypothesis: A neurochemical mediator destroys melanocytes or inhibits melanin production.
  • Oxidant-antioxidant mechanisms: An intermediate or metabolic product of melanin synthesis causes melanocyte destruction.
  • Intrinsic defect of melanocytes: Melanocytes have an inherent abnormality that impedes their growth and differentiation in conditions that support normal melanocytes.

Because none of these theories alone is entirely satisfactory, some have suggested a composite hypothesis. Diagnostic Considerations

Vitiligo and ocular disease
The uveal tract and retinal pigment epithelium contain pigment cells. Choroidal abnormalities have been reported in up to 30% of patients, and iritis has been reported in approximately 5% of patients. Exophthalmos may occur in the setting of concomitant Graves disease. Uveitis is the most significant ocular abnormality associated with vitiligo. The most severe form of uveitis is seen in the Vogt-Koyanagi-Harada syndrome. This syndrome is characterized by vitiligo, uveitis, aseptic meningitis, dysacusis, tinnitus, poliosis, and alopecia.
Alezzandrini syndrome includes facial vitiligo, poliosis, deafness, and unilateral visual changes. The affected eye has decreased visual acuity and an atrophic iris.[6]
Although the color of the irides does not change in patients with vitiligo, depigmented areas in pigment epithelium and choroid occur in up to 40% of patients.
Vitiligo and autoimmune disorders
Vitiligo is frequently associated with disorders of autoimmune origin, with thyroid abnormalities being the most common. Vitiligo usually precedes the onset of thyroid dysfunction. A study of 363 pediatric patients with both segmental and nonsegmental vitiligo was conducted at Fudan University in China. A significant incidence of thyroid dysfunction was found in patients with nonsegmental vitiligo. The authors suggested that it may be prudent to screen thyroid function and antibody levels in pediatric patients with vitiligo.[15]
Patients with autoimmune polyendocrinopathy candidiasis-ectodermal dystrophy have an increased prevalence of vitiligo. In this genetic syndrome, autoantibodies cause destruction of endocrine cells.[16]
Moreover, studies suggest that an association exists between a positive family history of vitiligo, autoimmune/endocrine diseases, leukotrichia, and an increased incidence of vitiligo in children. In addition, pediatric patients with a positive family history of vitiligo show an earlier age of disease onset.[17]
Vitiligo and auditory abnormalities[18]
Melanin may play a significant role in the establishment and/or maintenance of the structure and function of the auditory system and may modulate the transduction of the auditory stimuli by the inner ear.[19] The membranous labyrinth of the inner ear contains melanocytes, and the heaviest pigmentation is present in the scala vestibuli. Because vitiligo affects all melanocytes, auditory disturbances may result. Several studies have described familial vitiligo associated with hearing abnormalities and hypoacusis in 16% of patients younger than 40 years who have vitiligo.[19]
Vitiligo and melanoma[20, 21]
Vitiligolike depigmentation can occur in patients with malignant melanoma and is believed to result from a T-cell–mediated reaction to antigenic melanoma cells and cross-reactivity to healthy melanocytes. Most patients with melanoma or with vitiligo develop antibodies to similar antigens that are present both on melanocytes and on melanoma cells. These findings support the hypothesis that the clinical link between the 2 diseases results from immune responses to antigens shared by normal and malignant pigment cells. Studies have demonstrated that a halo nevus, hypopigmentation, or depigmentation may occur in patients with melanoma. The depigmentation or hypopigmentation spreads centrifugally from the trunk to other parts of the body. The sites of depigmentation may be remote from the original site of melanoma. Although metastasis has most likely occurred in the majority of patients, active vitiligo in these patients may signal a longer survival time than expected.
Laboratory Studies
Although the diagnosis of vitiligo generally is made on the basis of clinical findings, biopsy is occasionally helpful for differentiating vitiligo from other hypopigmentary disorders.
Vitiligo may be associated with other autoimmune diseases, especially thyroid disease and diabetes mellitus. Other associated autoimmune diseases include pernicious anemia, Addison disease, and alopecia areata. Patients should be made aware of signs and symptoms that suggest the onset of hypothyroidism, diabetes, or other autoimmune disease. If signs or symptoms occur, appropriate tests should be performed.[21]
Thyrotropin testing is the most cost-effective screening test for thyroid disease. Antinuclear antibody screening is also helpful. A CBC count with indices helps rule out anemia.
Clinicians should also consider investigating for serum antithyroglobulin and antithyroid peroxidase antibodies, particularly if thyroid involvement is suspected. Antithyroid peroxidase antibodies are regarded as a sensitive and specific marker of autoimmune thyroid antibodies. Screening for diabetes can be accomplished with fasting blood glucose or glycosylated hemoglobin testing.
Other Tests
Vitiligo is diagnosed by means of inspection with a Wood lamp.
Histologic Findings
Microscopic examination of involved skin shows a complete absence of melanocytes in association with a total loss of epidermal pigmentation. Superficial perivascular and perifollicular lymphocytic infiltrates may be observed at the margin of vitiliginous lesions, consistent with a cell-mediated process destroying melanocytes. Degenerative changes have been documented in keratinocytes and melanocytes in both the border lesions and adjacent skin. Other documented changes include increased numbers of Langerhans cells, epidermal vacuolization, and thickening of the basement membrane. Loss of pigment and melanocytes in the epidermis is highlighted by Fontana-Masson staining and immunohistochemistry testing.[22, 23]
Medical Care
No single therapy for vitiligo produces predictably good results in all patients; the response to therapy is highly variable. Treatment must be individualized, and patients should be made aware of the risks associated with therapy. During medical therapy, pigment cells arise and proliferate from the following 3 sources:
  • The pilosebaceous unit, which provides the highest number of cells, migrating from the external root sheath toward the epidermis
  • Spared epidermal melanocytes not affected during depigmentation[24]
  • The border of lesions, migrating up to 2-4 mm from the edge
Systemic phototherapy
Systemic phototherapy induces cosmetically satisfactory repigmentation in up to 70% of patients with early or localized disease.[21]
Narrow-band UV-B phototherapy is widely used and produces good clinical results. Narrow-band fluorescent tubes (Philips TL-01/100W) with an emission spectrum of 310-315 nm and a maximum wavelength of 311 nm are used. Treatment frequency is 2-3 times weekly, but never on consecutive days. This treatment can be safely used in children, pregnant women, and lactating women. Short-term adverse effects include pruritus and xerosis. Several studies have demonstrated the effectiveness of narrow-band UV-B therapy as monotherapy. A 2009 study concluded that oral vitamin E may represent a valuable adjuvant therapy, preventing lipid peroxidation in the cellular membrane of melanocytes and increasing the effectiveness of narrow-band UV-B therapy.[25]
UV-B narrow-band microphototherapy[26] is therapy targeting the specific small lesions. Selective narrow-band UV-B (311 nm) is used with a fiber optic system to direct radiation to specific areas of skin. Narrow-band UV-B has become the first choice of therapy for adults and children with generalized vitiligo.
Psoralen photochemotherapy involves the use of psoralens combined with UV-A light. Treatment with 8-methoxypsoralen, 5-methoxypsoralen, and trimethylpsoralen plus UV-A (PUVA) has often been the most practical choice for treatment, especially in patients with skin types IV-VI who have widespread vitiligo. Psoralens can be applied either topically or orally, followed by exposure to artificial UV light or natural sunlight. Vitiligo on the back of the hands and feet is highly resistant to therapy.
The best results from PUVA can be obtained on the face, trunk, and proximal parts of the extremities. However, 2-3 treatments per week for many months are required before repigmentation from perifollicular openings merges to produce confluent repigmentation. The total number of PUVA treatments required is 50-300. Repigmentation occurs in a perifollicular pattern.
The advantages of narrow-band UV-B over PUVA include shorter treatment times, no drug costs, no adverse GI effects (eg, nausea), and no need for subsequent photoprotection.
Laser therapy
Another innovation is therapy with an excimer laser, which produces monochromatic rays at 308 nm to treat limited, stable patches of vitiligo. This new treatment is an efficacious, safe, and well-tolerated treatment for vitiligo when limited to less than 30% of the body surface. However, therapy is expensive. Localized lesions of vitiligo are treated twice weekly for an average of 24-48 sessions.
According to studies from 2004 and 2007, combination treatment with 0.1% tacrolimus ointment plus the 308-nm excimer laser is superior to 308-nm excimer laser monotherapy for the treatment of UV-resistant vitiliginous lesions.[27, 28]
A retrospective chart and photographic review of 80 patients concluded that segmental vitiligo has a better repigmentation response with excimer laser treatment used at earlier stages of the disease.[29] The study also concluded that long-term use and high cumulative UV energy of the excimer laser had better response.
Steroid therapy
Systemic steroids (prednisone) have been used, although prolonged use and their toxicity are undesirable.[30] Steroids have been reported anecdotally to achieve success when given in pulse doses or low doses to minimize adverse effects. The benefits versus the toxicity of this therapy must be weighed carefully. More research is necessary to establish the safety and effectiveness of this therapy for vitiligo.
A topical steroid preparation is often chosen first to treat localized vitiligo because it is easy and convenient for both doctors and patients to maintain the treatment. The results of therapy have been reported as moderately successful, particularly in patients with localized vitiligo and/or an inflammatory component to their vitiligo, even if the inflammation is subclinical.
In general, intralesional corticosteroids should be avoided because of the pain associated with injection and the risk of cutaneous atrophy.
Topical therapies
Topical tacrolimus ointment (0.03% or 0.1%) is an effective alternative therapy for vitiligo, particularly when the disease involves the head and neck. Combination treatment with topical tacrolimus 0.1% plus the 308-nm excimer laser is superior to monotherapy with the 308-nm excimer laser monotherapy for UV-resistant vitiliginous lesions. On the face, narrow-band UV-B works better if combined with pimecrolimus 1% cream rather than used alone.[31, 32]
A 2009 study out of Kerman Medical University in Iran showed that a combination of pimecrolimus 1% cream and microdermabrasion enhanced response time and repigmentation rates in children with vitiligo.[33]
Vitamin D analogs, particularly calcipotriol and tacalcitol, have been used as topical therapeutic agents in vitiligo. They target the local immune response and act on specific T-cell activation. They do this by inhibition of the transition of T cells (early to late G1 phase) and inhibition of the expression of various proinflammatory cytokines that encode tumor necrosis factor-alpha and interferon gamma. These vitamin D3 compounds influence melanocyte maturation and differentiation, in addition to up-regulating melanogenesis through pathways that are activated by specific ligand receptors (eg, endothelin receptor and c-kit).[34] The combination of topical calcipotriene and narrow-band UV-B or PUVA results in improvement appreciably better than that achieved with monotherapy.
Use of khellin 4% ointment and monochromatic excimer light (MEL) 308 nm has been investigated. Forty-eight patients with vitiligo were randomized to 3 groups. Group I included 16 patients treated with MEL 308 nm once weekly and oral vitamin E; group II included 16 patients treated with MEL 308 nm once weekly combined with khellin 4% ointment (MEL-K) and oral vitamin E; group III (control group) included 16 patients treated only with oral vitamin E. Efficacy was assessed at the end of 12 weeks based on the percentage of repigmentation. The clinical response achieved in groups I and II was higher compared with group III (control group), without showing significant differences. Use of khellin 4% may me a valid therapeutic option worthy of consideration in the treatment of vitiligo.[35]
Depigmentation therapy
If vitiligo is widespread and attempts at repigmentation do not produce satisfactory results, depigmentation may be attempted in selected patients.
The long-term social and emotional consequences of depigmentation must be considered. Depigmentation should not be attempted unless the patient fully understands that the procedure generally results in permanent depigmentation. Some authorities have recommended consultation with a mental health professional to discuss potential social consequences of depigmentation.
A 20% cream of monobenzylether of hydroquinone is applied twice daily for 3-12 months. Burning or itching may occur. Allergic contact dermatitis may be seen.[36]
Topical PUVA is of benefit in some patients with localized lesions. Cream and solution of 8-methoxypsoralen (0.1-0.3% concentration) are available for this treatment.[6] It is applied 30 minutes prior to UV-A radiation (usually 0.1-0.3 J/cm2 UV-A) exposure. It should be applied once or twice a week. Physicians who prescribe PUVA therapy should be thoroughly familiar with the risks associated with the treatment. Additional UV-A exposure should be avoided while skin is sensitized because severe burns may occur if patients receive additional UV-A exposure. Sunscreens should be given to all patients with vitiligo to minimize risk of sunburn or repeated solar damage to depigmented skin. Patients must understand that most sunblocks have a limited ability to screen UV-A light.
Of general concern, tanning of surrounding normal skin exaggerates the appearance of vitiligo, and this is prevented by sun protection. Sunscreens with a sun protection factor of 15 or higher are best.
A clinical guideline summary from the British Association of Dermatologists, Guideline for the diagnosis and management of vitiligo, may be of interest.[34]
Surgical Care
Surgical alternatives exist for the treatment of vitiligo; however, because of the time-consuming nature of surgical therapies, these treatment regimens are limited to segmental or localized vitiligo. Unilateral (segmental) vitiligo has been shown as the most stable form, responding well to surgical interventions in numerous studies. Such areas as dorsal fingers, ankles, forehead, and hairline tend to not repigment well. Patients who have small areas of vitiligo with stable activity are candidates for surgical transplants. The most important factors indicating stability are as follows:
  • No progression of lesions for at least 2 years
  • Spontaneous repigmentation indicates vitiligo inactivity
  • A positive minigrafting test disclosing repigmentation at 4-5 minigrafts, which, to date, is the most accurate evidence of vitiligo stability
  • Absence of new koebnerization, including the donor site for the minigrafting test
  • Unilateral vitiligo most stable form of vitiligo[37]
Five basic methods for repigmentation surgery have been described, as follows[38, 39] :
  • Noncultured epidermal suspensions: After the achromic epidermis is removed, an epidermal suspension with melanocytes and keratinocytes previously prepared by trypsinization of normally pigmented donor skin is spread onto the denuded area and immediately covered with nonadherent dressings. Using noncultured epidermal cellular grafts, 71% of patients in one study achieved more than 75% repigmentation, especially in segmental vitiligo, piebaldism, and halo nevi.[40] Color mismatches were common, and generalized vitiligo did not repigment quite as well.
  • Thin dermoepidermal grafts: The depigmented epidermis is removed by superficial dermabrasion, including the papillary dermis, and very thin dermoepidermal sheets harvested with dermatome are grafted onto the denuded skin.
  • Suction epidermal grafting: Epidermal grafts can be obtained by vacuum suction, usually with 150 mm Hg. The recipient site can be prepared by suction, freezing, or dermabrasion of the sites 24 hours before grafting. The depigmented blister roof is discarded, and the epidermal donor graft is placed on the vitiliginous areas.
  • Punch minigrafting: Small donor grafts are inserted into the incision of recipient sites and held in place by a pressure dressing. The graft heals readily and begins to show repigmentation within 4-6 weeks. Some pebbling persists but is minimal, and the cosmetic result is excellent.
  • Cultured epidermis with melanocytes or cultured melanocyte suspensions: Depigmented skin is removed using liquid nitrogen, superficial dermabrasion, thermosurgery, or carbon dioxide lasers; very thin sheets of cultured epidermis are grafted or suspensions are spread onto the denuded surface.[37]
Micropigmentation[41] is another option. Tattooing can be used to repigment depigmented skin in dark-skinned individuals. Color matching is difficult, and the color tends to fade. Skin can be dyed with dihydroxyacetone preparations, although the color match is often poor.
Long-term results of 2-mm punch grafts in patients with generalized vitiligo and segmental vitiligo were assessed. In patients with generalized vitiligo (61 lesions), 28% had excellent repigmentation, 23% had good repigmentation, 23% had fair repigmentation, and 26% had poor repigmentation. In patients with segmental vitiligo (9 lesions), 78% had excellent repigmentation. Twenty-seven percent of the 70 patients had a cobblestonelike effect. The authors suggested that to prevent a cobblestonelike event, use of smaller grafts may be helpful.[42]
Consultations
Consultation with an ophthalmologist is warranted. Additionally, psychological needs must be addressed on a continual basis with appropriate referrals to mental health specialists.[8]
Medication Summary
The goals of pharmacotherapy are to reduce morbidity and to prevent complications.
Corticosteroids
Class Summary
Corticosteroids have anti-inflammatory properties and cause profound and varied metabolic effects. In addition, these agents modify the body's immune response to diverse stimuli. These drugs are used to stop spread of vitiligo and accomplish repigmentation. Data supporting the efficacy of such treatment is largely anecdotal. More study is needed to establish the safety and efficacy of systemic agents.
 A medium potency topical steroid. Treats inflammatory dermatosis responsive to steroids. Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing capillary permeability.
 An adrenocorticosteroid derivative suitable for application to skin or external mucous membranes. Has mineralocorticoid and glucocorticoid effects resulting in relieve of pruritus.
 Class I superpotent topical steroid; suppresses mitosis and increases synthesis of proteins that decrease inflammation and cause vasoconstriction. Decreases inflammation by stabilizing lysosomal membranes, inhibiting PMN and mast cell degranulation.
Psoralens
Class Summary
These agents are used with UV-A exposure for the treatment of localized or generalized vitiligo.

Inhibits mitosis by covalently binding to pyrimidine bases in DNA when photoactivated by UV-A. Effective in treating hyperkeratosis.
Trioxsalen (Trisoralen)

For treatment of hyperkeratosis. In UV-A radiation, inhibits mitosis by covalently binding to pyrimidine bases in DNA.
Immunomodulator
Class Summary
Immunomodulators suppress the activity of the immune system.

The mechanism of action of tacrolimus in atopic dermatitis is not known. Reduces itching and inflammation by suppressing the release of cytokines from T cells. Also inhibits transcription for genes that encode IL-3, IL-4, IL-5, GM-CSF, and TNF-alpha, all of which are involved in the early stages of T-cell activation. Additionally, may inhibit release of pre-formed mediators from skin mast cells and basophils, and downregulate expression of FCeRI on Langerhans cells. Can be used in patients as young as 2 years old. Drugs of this class are more expensive than topical corticosteroids. It is available as an ointment in concentrations of 0.03 and 0.1%.
Vitamins
Class Summary
Vitamin D analogs may regulate skin cell production and differentiation.
Synthetic vitamin D-3 analog that regulates skin cell production and development. Inhibits epidermal proliferation, promotes keratinocyte differentiation, and has immunosuppressive effects on lymphoid cells. Used in the treatment of moderate plaque psoriasis. Use 0.005% cream, ointment, or solution.

Topical Inflammatory Dermatoses

Cream/Ointment (0.025%): Apply BID-QID
Cream/Ointment (0.1%, 0.5%): Apply BID-TID
Spray: Apply TID-QID
See also combo with nystatin

Oral Inflammatory or Ulcerative Lesions

Dental Paste: Apply as thin film qHS; may increase to BID/TID PC

Topical Inflammatory Dermatoses

Cream/Ointment (0.025%): Apply BID-QID
Cream/Ointment (0.1%, 0.5%): Apply BID-TID
Spray: Apply TID-QID
Limit to the minimum amount necessary for therapeutic efficacy
See also combo with nystatin

Oral Inflammatory or Ulcerative Lesions

Dental Paste: Apply as thin film qHS; may increase to BID/TID PC

Corticosteroid-responsive Dermatoses

Relief of inflammatory and pruritic manifestations
Apply BID-QID

Other Indications & Uses

Inflammatory/pruritic dermatoses, eczemas, lichen planus, burns (1st and 2nd degree)
Adjunctive treatment for: alopecia areata, chronic discoid lupus erythematosus, dysidrosis, familial benign pemphigus, mycosis fungoides, nodular prurigo, psoriasis, seborrheic dermatitis

Corticosteroid-responsive Dermatoses

Relief of inflammatory and pruritic manifestations
Limit to the minimum amount necessary for therapeutic efficacy
Apply BID-QID

Corticosteroid-Responsive Dermatoses

Apply thin layer to affected areas BID and rub in gently and completely

Other Indications & Uses

Inflammatory/pruritic dermatoses, eczemas, lichen planus, burns (1st and 2nd degree)
Adjunctive treatment for: alopecia areata, chronic discoid lupus erythematosus, dysidrosis, familial benign pemphigus, mycosis fungoides, nodular prurigo, psoriasis, seborrheic dermatitis

Corticosteroid-Responsive Dermatoses

Apply thin layer to affected areas BID and rub in gently and completely; avoid face
Very high potency: Use minimum amount for therapeutic efficacy for shortest time possible

Vitiligo

PO
  • 20 mg with milk or food 2-4 hr before UV exposure
  • UV exposure: initial 15-25 min (based on skin color); add 5 min on each subsequent exposure (qOD) up to erythema/tenderness tolerance
Topical
  • Apply 1% lotion to affected area 2 hr before UV exposure q3-7 days

Psoriasis

Take PO with milk or food 2 hr before UVA exposure (qOD)
Body weight guidelines
  • <30 kg: 10 mg
  • 30-50 kg: 20 mg
  • 51-65 kg: 30 mg
  • 66-80 kg: 40 mg
  • 81-90 kg: 50 mg
  • 91-115 kg: 60 mg
  • >115 kg: 70 mg
May increase dose by 10 mg after 15 therapy sessions (do not increase any more than this)

Cutaneous T-Cell Lymphoma

PO
  • Take PO with milk or food 2 hr before UVA exposure
  • Initial dose 0.6 mg/kg
  • If serum concentration <50 ng/mL, administer initial dose + 10 mg after 24 hr
Parenteral
  • Inject 200 mcg (10 mL) into photoactivation bag of UVAR photopheresis system
  • Treatment on two consecutive days q 4 weeks for a min. of 7 treatment cycles

Systemic Sclerosis (Orphan)

Uvadex indicated in conjunction with the UVAR photopheresis to treat diffuse systemic sclerosis
Orphan indication sponsor
  • Therakos, Inc; Oaklands Corporate Center; 437 Creamery Way; Exton, PA 19341"

Cardiac Allograft Rejection (Orphan)

Uvadex designated orphan indication for prevention of acute rejection of cardiac allografts
Orphan indication sponsor
  • Therakos, Inc; Oaklands Corporate Center; 437 Creamery Way; Exton, PA 19341"

Graft Versus Host Disease (Orphan)

For use in conjunction with the UVAR photopheresis system to treat GVHD
Orphan indication sponsor
  • Therakos, Inc; Oaklands Corporate Center, 437 Creamery Way; Exton, PA 19341

Other Information

See Manufacturer label for complete UVA therapy information

<12 yeaAtopic Dermatitis

0.03% or 0.1% ointment: Apply thin layer to affected area BID
rs old: safety and efficacy not established

Atopic Dermatitis

0.03% ointment: Apply thin layer to affected area BID
<2 years old: Not recommended

Dosing Forms & Strengths

Moderate Plaque Psoriasis

Ointment/Cream
  • Apply thin layer to affected skin BID
Solution
  • Apply to affected scalp BID
Foam
  • Apply thin layer topically to affected skin BID

Administration

Rub in gently and completely
May use for up to 8 weeks

Other Information

Foam is flammable, contents under pressure, do not expose to heat or store at temperatures above 120 degrees F
Safety and efficacy not established




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