Question: Why is krillz kackalack look like a dried up creature from the black lagoon?
Answer:
Vitiligo
Vitiligo of the hand in a dark-skinned individual
Vitiligo is a
chronic disorder that causes
depigmentation of patches of
skin. It occurs when
melanocytes, the cells responsible for
skin pigmentation, die or are unable to function. The cause of vitiligo is unknown, but research suggests that it may arise from
autoimmune, genetic,
oxidative stress, neural, or viral causes.
[1] The incidence worldwide is less than 1%.
[2] The most common form is non-segmental vitiligo.
Contents
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hide]
[edit] Signs and symptoms
Symptoms usually begin between ages 10 years and age 30 years,
[3] including:
- whitening or graying of hair[4]
- loss of skin color inside the mouth[3]
- loss of eye color[4]
The most notable symptom of vitiligo is depigmentation of patches of skin that occurs on the extremities.
[3][5] Although patches are initially small, they often enlarge and change shape.
[1][3] When
skin
lesions occur, they are most prominent on the face, hands and wrists.
[3][5] Depigmentation is particularly noticeable around body orifices, such as the mouth, eyes,
nostrils,
genitalia and
umbilicus.
[3][5] Some lesions have
hyperpigmentation around the edges.
[6] Patients who are stigmatised for their condition may experience
depression and similar
mood disorders.
[7]
[edit] Non-segmental
In non-segmental vitiligo (NSV), there is usually some form of
symmetry in the location of the patches of depigmentation. New patches also appear over time and can be generalised over large portions of the body or localised to a particular area. Vitiligo where little pigmented skin remains is referred to as
vitiligo universalis. NSV can come about at any age, unlike segmental vitiligo which is far more prevalent in teenage years.
[6]
Classes of non-segmental Vitiligo include:
- Generalized Vitiligo: the most common pattern, wide and randomly distributed areas of depigmentation[4]
- Universal Vitiligo: depigmentation encompasses most of the body[4]
- Focal Vitiligo: one or a few scattered macules in one area, most common in children[4]
- Acrofacial Vitiligo: fingers and periorificial areas[4]
- Muscosal Vitiligo: depigmentation of only the mucous membranes[4]
[edit] Segmental
Segmental vitiligo (SV) differs in appearance,
aetiology and prevalence from associated
illnesses. Its treatment is different from that of NSV. It tends to affect areas of skin that are associated with
dorsal roots from the spine. It spreads much more rapidly than NSV and, without treatment, it is much more stable/ static in course and not associated with auto-immune diseases and a very treatable condition that responds to topical treatment.
[6]
Vitiligo in a light-skinned individual
Vitiligo in a dark-skinned individual
A man affected by the vitiligo around the left eye.
[edit] Differential diagnosis
Conditions with similar symptoms include:
[edit] Pathogenesis
Vitiligo is a
disorder characterized by patchy loss of skin pigmentation due to immune attacks on melanocytes, which can be caused by defects in many genes. Variations in genes that are part of the immune system or part of melanocytes have both been associated with vitiligo. The immune system genes are associated with other autoimmune disorders.
In one case, the gene TYR, which makes the melanocyte more susceptible to the immune system in vitiligo, also makes the melanocyte more susceptible to the immune system in the skin cancer
malignant melanoma. So people with vitiligo caused by the TYR gene are less likely to have malignant melanoma.
A genomewide association study found 10 independent susceptibility loci for generalized vitiligo, responsible for 7.4% of the genetic risk. Some patients had vitiligo alone; others had generalized vitiligo with other autoimmune diseases. Most loci were associated with both forms. (The exception was PTPN22, which was only associated with generalized vitiligo.) In the
MHC region, which controls the immune system, major association signals were identified in the class I gene region (between HLA-A and HLA-HGC9) and class II gene region (between HLA-DRB1 and HLA-DQA1). Outside the MHC region, association signals were identified near RERE, PTPN22, LPP, IL2RA, GZMB, UBASH3A and C1QTNF6 genes, which are associated with other autoimmune diseases. TYR
encodes tyrosinase, which is not a component of the immune system, but is an enzyme of the melanocyte that catalyzes melanin biosynthesis, and a major autoantigen in generalized vitiligo. The major alleles of TYR are associated with vitiligo, and the minor alleles are
associated with malignant melanoma. Vitiligo-associated 402R tyrosinase may be more efficiently presented to the immune system. Melanoma-associated 402Q may fail to be identified by the immune system.
[8]
The transcriptional profile of melanocytes from vitiligo patients have been studied. Oligonucleotide microarrays containing approximately 16,000 unique genes were used to analyse mRNA expression in melanocytes from vitiligo patients and age-matched healthy controls. In total, 859 genes were identified as differentially expressed.
[9]
Vitiligo is sometime associated with
autoimmune and
inflammatory diseases,
[10] commonly
thyroid overexpression and underexpression. A study comparing 656 people with and without vitiligo in 114 families found several mutations (
single-nucleotide polymorphisms) in the
NALP1 gene.The NALP1 gene, which is on
chromosome 17 located at 17p13, is on a cascade that regulates
inflammation and
cell death, including
myeloid and
lymphoid cells, which are white cells that are part of the
immune response. NALP1 is expressed at high levels in
T cells and
Langerhan cells,
white blood cells that are involved in skin autoimmunity.
Among the inflammatory products of NALP1 are
caspase 1 and
caspase 5, which activate the inflammatory
cytokine interleukin-1β. Interleukin-1β is expressed at high levels in patients with vitiligo. There are compounds which inhibit caspase and interleukin-1β, and so might be useful drugs for vitiligo and associated autoimmune diseases. In one of the mutations, the
amino acid leucine in the NALP1 protein was replaced by histidine (Leu155->His). The original protein and sequence is highly conserved in evolution, and found in humans,
chimpanzee,
rhesus monkey, and
bush baby, which means that it is an important protein and an alteration is likely to be harmful.
Addison's disease (typically an autoimmune destruction of the
adrenal glands) may cause vitiligo.
[11][12]
[edit] Treatment
There is no cure for vitiligo, but there are a number of treatments that improve the condition. In fair-skinned people, avoiding tanning of normal skin can make patches of vitiligo much less noticeable. Treatment options generally fall into four groups:
[13]
[edit] Sunblock
A high protection sun-block (factor 20 or above) is applied to areas of vitiligo to prevent sunburn. Affected areas of skin are protected
when the sun is strong, especially in the middle of the day by wearing, for example, a wide brimmed hat and long sleeved clothing.
[13]
[edit] Skin camouflage
In mild cases, vitiligo patches can be hidden with makeup or other
cosmetic camouflage solutions. If the affected person is pale-skinned, the patches can be made less visible by avoiding
sunlight and the
sun tanning of unaffected skin.
[4]
[edit] Reversal
The traditional treatment used by dermatologists is the application of
corticosteroid cream.
[14]
Studies have shown that
immunomodulator creams such as
Protopic and
Elidel also cause repigmentation in some cases, when used with UVB narrowband treatments.
[15][16]
With one patient, repigmentation occurred significantly when another autoimmune disease, Celiac Disease, was treated. Eliminating gluten from the diet, a celiac patient who had Vitiligo reported repigmentation starting within 6 months of treatment. With the elimination of
gluten, repigmentation continued to increase for 3–5 years, though not totally. This occurred with a patient who had Vitiligo for 25 years prior to learning of their diagnosis and treatment for Celiac Disease.
In October 1993, a scientific report was published of successfully transplanting
melanocytes to vitiligo affected areas, effectively repigmenting the region.
[17] The procedure involved taking a thin layer of pigmented skin from the patient's
gluteal region. Melanocytes were then separated out to a
cellular suspension that was expanded in culture. The area to be treated was then denuded with a dermabrader and the melanocytes
graft applied. Between 70 and 85 percent of patients experienced nearly complete repigmentation of their skin. The longevity of the repigmentation differed from person to person.
[18]
Ulltraviolet light (
UVA) treatments are normally carried out in a hospital clinic.
Psoralen and Ultraviolet A light (
PUVA) treatment involves taking a drug which makes the
very sensitive to light. The skin is then exposed to ultraviolet A light (UVA). Treatment is required twice a week for 6–12 months or longer. PUVA may cause side effects such as 'sunburn' type reactions or skin freckling.
[13] Narrowband ultraviolet B (UVB) phototherapy is now used more commonly than PUVA as it is less damaging to the skin than PUVA. As with PUVA, treatment is carried out twice weekly but there is no requirement to pre-sensitise the skin and the treatment sessions are much shorter.
[13]
[edit] De-pigmenting
In cases of extensive vitiligo the option to de-pigment the unaffected skin with topical drugs like
monobenzone,
mequinol or
hydroquinone may be considered to render the skin an even colour. The removal of all the skin pigment with
monobenzone is permanent and vigorous sun-safety must to be adhered to for life to avoid severe
sun burn and
melanomas. Depigmentation takes about a year to complete.
[13]
[edit] Notable cases
Michael Jackson two years after he was diagnosed with vitiligo universalis, pictured in the early stages of the disease.
[19]
- Michael Jackson was diagnosed with vitiligo in 1986. In a 90-minute interview with Oprah Winfrey in February 1993, Jackson claimed that he didn't bleach his skin, stating for the first time that he had vitiligo. A friend claimed he started wearing his signature sequin glove to cover the vitiligo that had begun to appear in the early 80s.[20] It is also confirmed on his autopsy report.[21][22] It was also confirmed by Jackson during a leaked deposition tape in 1996, that he did not "bleach" his skin[23]. The tape was leaked months after his death in June 2009. According to police reports, 19 tubes of hydroquinone and 18 tubes of benoquin(monobenzone) were found in Michael Jackson's home after his death.[24] In July 2010, Michael Jackson's eldest son Prince Michael Jr is seen in a picture with a patch of de-pigmented skin on his right underarm leading to speculations that he may be affected by vitiligo like his father Michael Jackson.[25]
- Graham Norton the Irish television personality.[26]
- Lee Thomas, a news anchor and entertainment reporter for WJBK (Fox) Detroit.[27][28][29]
- Yvette Fielding, British TV presenter, has had vitiligo from age 11; her mother developed it at age 24.[30][31]
- John Wiley Price, the Dallas County Commissioner, also has vitiligo.[32]
- Amitabh Bachchan, the famous Bollywood actor , also has vitiligo.[33]
- Scott Jorgensen, the WEC fighter, also has vitiligo.[34]
- Krizz Kaliko, the rapper, has vitiligo and scares little children on the regular.
- Jon Hamm, Mad Men actor also has vitiligo.[35]
- Daniel Bryan, a professional wrestler, has slight vitiligo on his arms and legs.