76: Vitiligo Flashcards
What is vitiligo and how is it characterized?
Vitiligo is an acquired skin disease characterized by progressive loss of melanocytes, leading to well-defined milky-white macules that may also include white hairs or poliosis.
At what age does vitiligo typically begin and how does its prevalence change with age?
Vitiligo can begin at any age but usually starts before the third decade of life. Almost half of patients present before the age of 20 years, and a third before 12 years. The prevalence of vitiligo gradually increases with age.
What are the psychological impacts of vitiligo on patients?
Vitiligo is often psychologically devastating for patients, significantly impacting their quality of life. Patients may experience mental impairment similar to that seen in conditions like psoriasis and atopic dermatitis.
What are the common clinical features and presentation patterns of vitiligo?
Vitiligo lesions are asymptomatic, white, nonscaly macules and patches with distinct margins that fluoresce under a Wood lamp. They can involve any part of the body, usually with a symmetrical distribution. Initial sites often include the face, acral, and genital areas.
What are the different variants of vitiligo and their characteristics?
Variant | Characteristics |
|————————-|———————————————————————————|
| Segmental vitiligo | Affects only one side of the body, tends to occur earlier in life. |
| Acrofacial vitiligo | More common in adults, typically involves hands, feet, and face, may evolve to generalized vitiligo. |
| Vitiligo universalis | Rare form affecting greater than 80% of body surface area, usually seen in adults.
How does the age of onset of vitiligo differ between the segmental variant and the generalized form?
The segmental variant of vitiligo tends to occur earlier in life, often before the age of 12, while the generalized form usually starts before the third decade of life. This difference in age of onset may influence patient management strategies.
What are the clinical features of vitiligo lesions?
Vitiligo lesions are characterized as asymptomatic, white, nonscaly macules and patches with distinct margins. The presentation varies by form: 1. Acrofacial vitiligo: Involves the hands, feet, and face, often evolving to generalized vitiligo. 2. Vitiligo universalis: Affects greater than 80% of the body surface area and is typically seen in adults.
Discuss the historical references to vitiligo and their significance.
Historical references to vitiligo date back to 1500 BC, with mentions in the Ebers Papyrus and the Bible. These texts describe skin diseases affecting color, indicating that vitiligo was recognized as a condition that could render individuals unclean.
What is the Koebner phenomenon in relation to vitiligo?
The Koebner phenomenon is an isomorphic response where depigmentation occurs readily at the site of skin trauma in patients with active vitiligo.
What are the characteristics of segmental vitiligo?
Segmental vitiligo is seen in 10-15% of patients and is characterized by unilateral and segmental or block-shaped distribution of lesions. It typically involves a single contiguous segment and often shows early involvement of the follicular melanocyte reservoir, resulting in poliosis.
What is the significance of the VIDA score in vitiligo?
The VIDA score is a 6-point scale developed to assess and monitor vitiligo activity. It defines active vitiligo as the spread of existing lesions or the onset of new lesions.
What are some disease associations with vitiligo?
Vitiligo is associated with an increased incidence of several autoimmune diseases, including type 1 diabetes, autoimmune thyroiditis, pernicious anemia, Addison disease, lupus, and alopecia areata.
What are the competing hypotheses regarding the etiology of vitiligo?
The etiology of vitiligo includes several competing hypotheses: 1. Autoimmune hypothesis: CD8+ T cells target and destroy melanocytes. 2. Cellular stress hypothesis: Cellular stress causes degeneration of melanocytes. 3. Chemical toxicity hypothesis: Chemical toxicity leads to melanocyte death. 4. Neural changes hypothesis: Neural changes affect melanocyte function.
A 25-year-old patient with vitiligo reports rapid progression of depigmentation after a minor skin injury. What phenomenon is likely responsible?
The Koebner phenomenon, or isomorphic response, is likely responsible. It occurs when depigmentation develops at the site of skin trauma in patients with active vitiligo.
A patient with vitiligo is concerned about developing other autoimmune diseases. What tests should be recommended?
Testing for TSH is recommended to rule out autoimmune thyroid disease, as up to 20% of vitiligo patients have at least one additional autoimmune disease.
What is the significance of the Koebner phenomenon in assessing vitiligo disease activity?
The Koebner phenomenon indicates that depigmentation occurs readily at the site of skin trauma in patients with active vitiligo. This response is used as a marker of disease activity.
How does the presence of trichrome vitiligo relate to disease activity?
Trichrome vitiligo is characterized by the blurring of lesional borders due to a hypopigmented zone between depigmented and normally pigmented skin. This condition is associated with active, rapidly spreading vitiligo.
What are the implications of the VIDA score in monitoring vitiligo?
The VIDA score is a 6-point scale developed to assess and monitor vitiligo activity, providing a quantifiable measure of disease progression.
What autoimmune diseases are commonly associated with vitiligo?
Vitiligo is associated with an increased incidence of several autoimmune diseases, including type 1 diabetes, autoimmune thyroiditis, pernicious anemia, Addison disease, lupus, and alopecia areata.
What are the potential complications associated with vitiligo?
Complications of vitiligo can include sensorineural hearing loss, ocular abnormalities, and syndromes like Vogt-Koyanagi-Harada syndrome and Alezzandrini syndrome.
Discuss the competing hypotheses regarding the etiology of vitiligo and their clinical implications.
The etiology of vitiligo is primarily understood as an autoimmune disease where CD8+ T cells target and destroy melanocytes. Other hypotheses suggest that cellular stress, chemical toxicity, and neural changes may also contribute.
What role do CD8+ T cells play in the pathogenesis of vitiligo?
CD8+ T cells are critical immune effectors that infiltrate the lesional epidermis and mediate cytotoxicity, leading to the destruction of melanocytes in vitiligo patients.
What is the convergence theory in relation to vitiligo?
The convergence theory suggests that multiple hypotheses regarding the pathogenesis of vitiligo may synergize to cause the disease.
How does the segmental variant of vitiligo differ from other forms?
The segmental variant of vitiligo rarely follows dermatomes and often crosses these zones, resulting from an autoimmune predisposition combined with melanocyte mutations.
What are the risk factors associated with developing vitiligo?
Risk factors for developing vitiligo include family history, genetic predisposition, and approximately 50 genetic loci influencing cellular apoptosis pathways and melanocyte function.
What is the significance of IFN-g in the context of vitiligo?
IFN-g is secreted by melanocyte-reactive autoimmune CD8+ T cells and induces the production of chemokines from keratinocytes, promoting the recruitment of additional T cells.
What are the clinical characteristics of vitiligo?
Vitiligo is characterized by well-defined, symmetrical depigmented lesions that can appear on any part of the body, with a preference for the face, genitals, and acral areas.
How can Wood lamp examination assist in diagnosing vitiligo?
Wood lamp examination in a dark room helps differentiate the depigmentation of vitiligo from hypopigmentation in other diseases.
What laboratory tests are relevant in the diagnosis of vitiligo?
Laboratory tests include TSH to rule out concomitant Hashimoto thyroiditis, and CBC and antinuclear antibody testing can be considered.
What histological findings are associated with vitiligo?
Histologic examination reveals a complete loss of melanocytes within the epidermis and an inflammatory infiltrate of CD4+ and CD8+ T cells.
What are some common differential diagnoses for vitiligo?
Common differential diagnoses include inherited hypomelanoses, pityriasis versicolor, postinflammatory hypopigmentation, hypopigmented mycosis fungoides, and lichen sclerosus et atrophicus.
A patient presents with asymptomatic, white, nonscaly macules on their hands and face. What diagnostic tool can help differentiate vitiligo from other hypopigmentation disorders?
A Wood lamp examination in a dark room can help differentiate vitiligo from other hypopigmentation disorders.
What are the key clinical features that differentiate vitiligo from other forms of hypopigmentation?
Vitiligo is characterized by well-defined, symmetrical depigmented lesions on any part of the body, especially the face, genitals, and acral areas.
How does the histological examination of vitiligo differ from other pigment disorders?
Histological examination in vitiligo reveals a complete loss of melanocytes within the epidermis and an inflammatory infiltrate of CD4+ and CD8+ T cells.
What laboratory tests are important in the diagnosis and management of vitiligo?
Key laboratory tests for vitiligo include TSH to rule out concomitant Hashimoto thyroiditis and CBC and antinuclear antibody testing.
What is the primary pathological change in vitiligo?
Loss of melanocytes within the epidermis.
What type of immune cells are involved in vitiligo?
Inflammatory infiltrate of CD4+ and CD8+ T cells in an interface pattern, primarily with CD8+ T cells infiltrating the epidermis.
What laboratory tests are important in the diagnosis and management of vitiligo?
Key laboratory tests for vitiligo include TSH to rule out concomitant Hashimoto thyroiditis, CBC, and antinuclear antibody testing in the context of light sensitivity.
What are the main differential diagnoses for vitiligo?
Main differential diagnoses include inherited hypomelanoses, piebaldism, tuberous sclerosis, pityriasis versicolor, postinflammatory hypopigmentation, hypopigmented mycosis fungoides, lichen sclerosus, and nevus depigmentosus.
What is the clinical course and prognosis of vitiligo?
Unpredictable course with cycles of flares and stability; repigmentation in hair-bearing areas is likely; lesions in glabrous skin respond more slowly; stress may trigger onset or relapse.
What are the management strategies for vitiligo?
Key factors include skin phototype, presence of halo nevi, disease duration, extent, and activity.
What are the benefits of topical corticosteroids in vitiligo treatment?
Good efficacy, ease of application, high compliance rate, low cost, and can be applied twice daily.
What are the drawbacks of topical corticosteroids in vitiligo treatment?
Skin atrophy, telangiectasia, hypertrichosis, acneiform eruptions, and striae.
What is the role of phototherapy in the treatment of vitiligo?
Full-body phototherapy is the first treatment option for patients with more than 5% body surface area affected; targeted phototherapy is for limited, focal disease.
What are the benefits of Narrowband Ultraviolet B (nbUVB) in vitiligo treatment?
Repigmentation and stabilization, which is crucial for patients with active disease.
What are the advantages of topical calcineurin inhibitors in vitiligo treatment?
Good efficacy, excellent safety profile, suitable for use on the face, neck, intertriginous areas, and in children.
What are the potential adverse effects of PUVA therapy?
Nausea, ocular damage, phototoxic reactions, and an increased risk of skin cancer.
What is the expected time frame for complete depigmentation with Monobenzone?
Complete depigmentation can take 1 to 2 years.
What psychological interventions have been shown to benefit patients with vitiligo?
Cognitive-behavioral therapy and hypnosis have been shown to improve quality of life and reduce anxiety.
What criteria should be met for surgical therapies in vitiligo treatment?
Surgery should be reserved for patients with highly stable disease, defined as the absence of new or growing lesions for 1 to 2 years.
What types of grafts are used in surgical therapies for vitiligo?
Surgical therapies may involve tissue grafts, including thin and ultrathin split-thickness skin grafts, suction blister epidermal grafts, mini punch grafts, and hair follicle grafts.
What is the recommended treatment frequency and dosage for nbUVB therapy in children with vitiligo?
2 to 3 times weekly, starting with a dose of 200 millijoules (mJ) and increasing by 10% to 20% increments.
What are the benefits of combination therapies in the treatment of vitiligo?
Combination therapies are considered the most effective treatment, allowing for selection of important sites for adjuvant topical therapy.
What is the recommended first treatment option for patients with vitiligo affecting more than 5% of body surface area?
Full-body phototherapy is the recommended first treatment option.
What is the reported repigmentation rate for nbUVB therapy when used alone?
Repigmentation rates range from 40% to 100%, depending on the location.
What is the recommended treatment frequency for nbUVB therapy?
nbUVB therapy should be administered 2 to 3 times weekly.
What is the minimal erythema dose in nbUVB therapy?
The minimal erythema dose is the lowest dose that results in visible erythema lasting less than 24 hours.
What is the role of oral steroids in combination therapy for vitiligo?
Oral steroids help control rapidly spreading vitiligo until phototherapy achieves a therapeutic dose.
What is the reported stabilization rate in children with twice-weekly nbUVB therapy?
Twice-weekly nbUVB therapy has been reported to achieve stabilization in 80% of children.
What is the expected duration of nbUVB therapy to achieve full repigmentation?
Typically requires 9 to 12 months or more.
What is the benefit of combining topical corticosteroids with nbUVB therapy?
The addition of topical corticosteroids has been reported to increase the benefit of nbUVB therapy.
What are the key considerations for using monobenzone in vitiligo treatment?
Monobenzone is used for widespread vitiligo; it can take 1 to 2 years for complete depigmentation, and patients must be counseled about lifelong sun sensitivity.
What specific therapies are often used in combination therapies for vitiligo?
Combination therapies may include any type of light therapy along with topical treatments.
What percentage of patients may develop contact dermatitis to vitiligo cream?
Up to 20% of patients may develop a contact dermatitis to the cream.
What must patients be counseled about regarding sun sensitivity?
Patients must be counseled that their skin will be sun-sensitive for life and that strict sun protection is necessary.
How do combination therapies enhance the treatment of vitiligo?
Combination therapies using any type of light are considered the most effective treatment for vitiligo.
What specific therapies are often used in combination with light therapy for vitiligo?
The combination of oral steroid pulse therapy (e.g., dexamethasone or prednisone) with light therapy is particularly helpful.
What psychological interventions improve quality of life in vitiligo patients?
Cognitive-behavioral therapy and hypnosis have been shown to improve quality of life, reduce anxiety, and enhance coping.
What criteria should be met before considering surgical therapies for vitiligo?
Surgery should be reserved for patients with highly stable disease, defined as the absence of new or growing lesions for 1 to 2 years.
What are the advantages of split-thickness grafting in vitiligo management?
Advantages: Easy and inexpensive.
What are the disadvantages of split-thickness grafting in vitiligo management?
Disadvantages: Frequently results in color mismatch and occasional failure of the graft.
What is the role of JAK inhibitors in the treatment of vitiligo?
JAK inhibitors, such as oral tofacitinib, oral ruxolitinib, and topical ruxolitinib, are reported to promote repigmentation.
How does blister grafting compare to punch grafting in terms of cosmetic results?
Blister grafting provides better cosmetic results without cobblestoning but is time-consuming and may be more difficult to perform.
What is the significance of afamelanotid in the treatment of vitiligo?
Afamelanotid is an α-melanocyte-stimulating hormone analog that increases the rate and extent of repigmentation when used with nbUVB.
What is the advantage of cellular grafts for segmental vitiligo?
Cellular grafts can cover larger surface areas with up to a 1:10 donor-to-recipient area ratio.
What is the reported effect of JAK inhibitors in vitiligo treatment?
JAK inhibitors have been reported to promote repigmentation in vitiligo patients.
What are the potential drawbacks of split-thickness grafting?
Split-thickness grafting frequently results in color mismatch and occasional graft failure.
What are the limitations of punch grafting in vitiligo treatment?
Punch grafting should be used in limited areas due to frequent side effects, such as cobblestoning.
What are the advantages and disadvantages of blister grafting?
Blister grafting provides better cosmetic results without cobblestoning but is time-consuming and may be more difficult to perform.
What is the role of afamelanotide in vitiligo treatment?
Afamelanotide increases the rate and extent of repigmentation when used with nbUVB therapy.
What is the advantage of melanocyte keratinocyte transplant procedures?
Melanocyte keratinocyte transplant procedures can cover larger surface areas and are becoming the first-line option in surgical management.
What are the advantages and disadvantages of using split-thickness grafting?
Advantages: Easy and inexpensive. Disadvantages: Frequently results in color mismatch and occasional failure of the graft.
How do JAK inhibitors contribute to vitiligo treatment?
JAK inhibitors are reported to promote repigmentation in vitiligo patients. Examples include oral tofacitinib, oral ruxolitinib, and topical ruxolitinib.
What is the role of afamelanotid in enhancing repigmentation?
Afamelanotid, when used with nbUVB, has been shown to increase the rate and extent of repigmentation.
Compare the effectiveness and challenges of punch grafting and blister grafting.
Grafting Type | Effectiveness | Challenges |
|———————|—————————————|———————————————-|
| Punch Grafting | Easy to perform and inexpensive | Limited use due to frequent side effects like cobblestoning |
| Blister Grafting | Better cosmetic results without cobblestoning | Time-consuming and may be more difficult to perform |
What are the distinguishing features of Piebaldism?
- White forelock
- Anterior body midline depigmentation
- Bilateral skin depigmentation present at birth
- Absence of melanocytes
- Autosomal dominant inheritance
What are the distinguishing features of Tuberosclerosis?
- White forelock and white skin macules (ash leaf)
- Angiomas appearing in childhood to early adolescence
- Fibrous plaques and hypopigmented ‘confetti’ macules appearing in early years
- Seizures and autosomal dominant inheritance
What are the distinguishing features of Tinea Versicolor?
- Well-demarcated finely scaling patches in highly sebaceous areas
- Yellow-green fluorescence on Wood light examination
What are the distinguishing features of Nevus Anemicus?
- Poorly demarcated white macule surrounded by erythema
- Disappears with diascopy
What are the distinguishing features of Nevus Depigmentosus?
- Well-delimited hypopigmented macule present at birth
- Irregular, saw-toothed border
- Hairs within the lesion generally remain pigmented
- Lesion size will expand in proportion to growth with age
What are the distinguishing features of Piebaldism and how does it differ from Waardenburg syndrome?
Piebaldism is characterized by:
- White forelock
- Anterior body midline depigmentation
- Bilateral skin depigmentation present at birth (absence of melanocytes)
- Autosomal dominant inheritance.
Waardenburg syndrome features:
- White forelock, white skin macules, hypertrichorism, heterochromic irises, deafness, early graying, and Hirschsprung disease.
How can you differentiate between Tinea Versicolor and Mycosis Fungoides?
Tinea Versicolor:
- Well-demarcated finely scaling patches in sebaceous areas.
- Yellow-green fluorescence on Wood light.
Mycosis Fungoides:
- Scattered irregular hypopigmented patches on non-sun-exposed areas.
- Atrophic epidermal surface with plaque and tumor lesions may be present.
What are the distinguishing features of Nevus depigmentosus compared to Nevus anemicus?
Nevus depigmentosus:
- Well-delimited hypopigmented macule surrounded by erythema, which disappears with diascopy.
- Present at birth with irregular, saw-toothed borders; hairs within the lesion generally remain pigmented.
Nevus anemicus:
- Poorly demarcated white macule surrounded by erythema, which disappears with diascopy.
