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Disturbances of Pigmentation. Boris Ioffe, D.O. Melanin. primary pigment producing brown coloration Tyrosine – tyrosinase –melanin- this occurs in the melanosomes of melanocytes

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melanin
Melanin
  • primary pigment producing brown coloration
  • Tyrosine – tyrosinase –melanin- this occurs in the melanosomes of melanocytes
  • Then the melanosomes are transferred from the melanocyte to a group of keratinocytes called the epidermal melanin unit (1:40)
  • Variations in skin color is related to
    • number of melanosomes
    • degree of melanization
    • distribution of the epidermal melanin unit
pigmentary demarcation lines
Pigmentary Demarcation Lines
  • Group A- outer upper arms with variable extension across the chest
  • Group B-posteromedial aspect of the lower limb – appear 1st time during pregnancy
  • Group C-Paired median or paramedian lines on the chest, with midline abdominal extension
  • Group D-medial, over the spine
  • Group E-bilaterally symmetrical, obliquely oriented, hypopigmented macules on the chest
normal pigmentation
Normal Pigmentation
  • Normal skin pigmentation is influenced by:
    • degree of vascularity
    • amount & location of melanin
    • presence of carotene
    • thickness of the horny layer
melanin production
Melanin Production
  • The amount produced is dependent on:
    • Genetics
    • amount and the wavelengths of ultraviolet light received
    • amount of melanocyte-stimulating hormone(MSH) secreted
    • effect of melanocyte stimulating chemicals like furocoumarins (psoralens)
hemosiderin hyperpigmnetation
Hemosiderin Hyperpigmnetation

Pigmentation due to deposits of hemosiderin occurs in: purpura, hemochromatosis, hemorrhagic dzs and stasis ulcers

  • difficult to distinguish from postinflammatory dermal melanosis clinically
postinflammatory hyperpigmentation
Postinflammatory Hyperpigmentation
  • Any inflammatory condition can cause either hypopigmentation or hyperpigmentation
  • Also may be a complication of chemical peels, dermabrasion, laser therapy, or liposuction
  • Histologically, there is melanin in the upper dermis and around upper dermal vessels, located primarily in melanophages
postinflammatory hyperpigmenation
Postinflammatory hyperpigmenation
  • Postinflammatory hyperpigmentation following resolution of lymphocytoma cutis on the cheek of a black child
industrial hyperpigmentation
Industrial Hyperpigmentation
  • Occurs in coal miners, anthracene workers, pitch workers, etc
  • Pigmentation of the face may occur from the incorporation in cosmetics of derivatives of coal tar, petrolatum, or picric acid, mercury, lead, bismuth, or furocoumarins (psoralens)
systemic diseases
Systemic Diseases
  • Syphilis, malaria, pellagra, and diabetes
  • Addison’s disease- diffuse melanosis pronounced in the axillae and palmar creases, and nipples and genitals, and buccal mucosa
  • Diabetes produces diffuse bronzing of the skin
  • ** patients with virilizing adrenal tumors usually develop hyperpigmentation and hypertrichosis
systemic diseases12
Nelson’s syndrome (a pituitary MSH-producing tumor)

Pheochromocytoma

Hemochromatosis

Amyloidosis

Scurvy

Pregnancy

Menopause

Porphyria cutanea tarda

Vitamin B12 deficiency

Kwashiorkor

Vitamin A deficiency

Primary biliary cirrhosis (triad= hyperpigmentation, pruritis, xanthomas)

Systemic Diseases
hemochromatosis
Characterized by:

Gray-brown mucocutaneous hyperpigmentation

Diabetes mellitus

hepatomegaly

Usually are present:

Cirrhoisis

Hypogonadism

Liver cirrhosis

Hemochromatosis
hemochromatosis14
Skin pigmentaion is usually generalized

But, more pronounced on face, extensor aspect of the forearms, backs of the hands, and the geniocrural area

Iron is deposited in the skin

Iron is present as granules around blood vessels and sweat glands and within macrophages

The actual pigmentation is caused by increased basal-layer melanin

Mucous memebranes are pigmented in up to 20% of patients

Koilonychia is present in 50%

Localized ichthyosis in 40%

Alopecia is common

Hemochromatosis
hemochromatosis tx
Hemochromatosis-tx
  • Phlebotomy until satisfactory iron levels are obtained
  • Extracorporeal chelation has also been used successfully
  • Associated DM requires medical tx
  • Long-term complications are cirrhosis and then hepatomas
melasma
Brown patches, sharply demarcated, typically on the malar prominences and forehead

The three clinical patterns are: centrofacial, malar, mandibular

Increased pigment may simultaneously occur around the nipples and external genitalia

Tends to affect the darker-complected

It may also be found on the forearms

Occurs at pregnancy and at menopause

It may also be seen in ovarian disorders and other endocrine disorders

Most frequently 90% of the time seen in women, 10% in men

Melasma
melasma18
Strong association with the use of OCs or dilantin

Discontinuing contraceptives rarely clears the pigmentation, and it may last for years after discontinuing them.

Melasma of pregnancy usually clears within a few months of delivery

Tx- avoid sunlight, and a complete sun block with broad-spectrum UVA coverage should be used daily

Kligman’s formula (Triluma)

> then 4% hydroquinone may be needed

Side effects of this is ochronosis and satellite pigmentation

Melasma
melasma19
Melasma
  • Jessner’s solution, glycolic acid peels,azelaic acid, kojic acid, and cystamine and buthionine sulfoximine are other options
acromelanosis progressiva
AKA acropigmentation

A progressive pigmentary disorder first described in a Japanese infant

Characterized by diffuse black pigmentation on the dorsum of all the fingers and toes

Pigmentation became progressively more widespread and more pigmented

By age 4 or 5 the perineum, extremities, and areas of the head and neck were involved

Epileptiform seizures occurred

History revealed consanguinity

Acromelanosis Progressiva
pigmented anomalies of the extremities
Acropigmentation of Dohi

Found to affect individuals from Europe, India, Caribbean

First described in Japan in 12 patients

AKA dyschromatosis symmetrica hereditaria or symmetrical dyschromatosis of the extremities

Patients develop progressive pigmented & depigmented macules

Often mixed in is a reticulate pattern

Many believe this to be a variation of acropigmentation of Kitamura

Pigmented Anomalies of the Extremities
reticular pigmented anomaly of the flexures
It begins age 20 to 30 yrs and progresses gradually

Unknown etiology

AD with variable penetrance and expressivity, and delayed onset

Many authors believe it is a spectrum of reticulate acropigmentation of Kitamura

Another manifestation of this disorder is familial-rocacea-like dermatitis with warty keratotic plaques on the trunk and limbs

There is no treatment

Reticular Pigmented Anomaly of the Flexures
histology
Histology
  • Distinctive elongation, tufting, and deep hyperpigmentation of therete ridges, with protrusion of similar tufts even from the sides of the follicles
reticulate acropigmentation of kitamura
AD

Characterized by linear palmar pits and pigmented macules 1-4 mm in diameter on the volar and dorsal aspects of the hands and feet

One report of a pt with bony abnormalities consisting of absence of terminal phalanges of the second, third, and fourth toes

Some tx success has been reported using axelaic acid ointment

Reticulate Acropigmentation of Kitamura
dermatopathia pigmentosa reticularis
Consists of a triad of generalized reticulate hyperpigmentation, noncicatricial alopecia, and onychodystrophy

Other associations: adermatoglyphia, hypohidrosis or hyperhidrosis, palmoplantar hyperkeratosis, and nonscarring blisters on dorsa of hands and feet.

An autosomal dominant inheritance pattern has been reported.

Dermatopathia Pigmentosa Reticularis
transient neonatal pustular melanosis
Infants develop 2- 3mm macules, pustules, and ruptured pustules at birth, predominantly involving the face

Pigmentation may last for weeks or months after the pustules are healed

Histologically, there are intracorneal or subcorneal aggregates of predominantly neutrophils, but eosinophils may also be found

Dermal inflammation is composed of an admixture of neuts and eos

Differential dx: ETN, neonatal acne, & acropustulosis of infancy

Transient Neonatal Pustular Melanosis
peutz jeghers
hyperpigmented macules on the lips and oral mucosa and polyposis of the small intestine

Dark brown or black macules appear typically on the lips, especially the lower lip, in infancy or childhood

Similar lesions may appear on buccal mucosa, tongue, gingiva, and genital mucosa

Associated polyposis involves the small intestine preferencely

But, hamartomatous polyps of the stomach and colon may occur

Symptoms of hamhartomas of the small intestine may cause repeated bouts of abdominal pain and vomiting, and intussusception

Peutz-Jeghers
peutz jeghers syndrome
Peutz-Jeghers syndrome
  • Lip lentigenes in an adolescent with Peutz-Jeghers syndrome
reihl s melanosis
Photosensitivity, phototoxic dermatitis

Begins with pruritis, erythema, and pigmentation, gradually spreads, then becomes stationary

Melanosis occurs mostly in women and develops over months

Characteristic feature is spotty light to dark brown pigmentation

Most intense on the forehead, malar regions, behind the ears, on the sides of the neck, on other sun-exposed areas

Also circumscribed telangiectasia and temporary hyperemia

Reihl’s Melanosis
tar melanosis
An occupational dermatosis occurring among tar handlers after years of exposure

Severe, widespread itching develops, followed by reticular pigmentation, telangiectases, and a shiny appearance of the skin

There is a tendency for hyperhidrosis

Small, dark, lichenoid, follicular papules become profuse on the extremities, namely the forearms

Bullae are sometimes observed

Represents a photosensitivity or phototoxicity induced by tar

Tar Melanosis
universal acquired melanosis carbon baby
Ruiz-Maldonado reported a case of a Mexican child, born white, who progressively became black

Developed pigmentation of the palms, soles, mucous membranes

EM showed a negroid pattern in the melanosomes of the epidermal melanocytes and keratinocytes

Melanocytes were not increased in number

Universal Acquired Melanosis(Carbon Baby)
periorbital hyperpigmentation
1.) Familial periorbital melanosis (AD)

Usually involves all four eyelids, may extend to involve the eyebrows and cheeks

2.) Erythema dyschromicum perstans is a rare cause

3.) Familial dark circles around the eyes, frequently seen in individuals of Mediterranean ancestry

Periorbital Hyperpigmentation
metallic discolorations
Metallic Discolorations
  • Pigmentation from deposition of fine metallic particles in the skin
  • Metal may be carried to skin from the blood stream or may permeate into it from surface applications
argyria
Localized or widespread slate-colored pigmentation

Due to silver in the skin

Most noticeable in parts exposed to sunlight

Tissue silver may stimulate melanocytes

Initially discoloration is hardly perceptible, having only a faint blue color, but a slate-gray color develops with time

Local tx with a silver-containing product may produce argyria

occupational exposure, usually siversmiths

In localized exposures, the appearance may be separated by many years from the exposure

Argyria
histology44
Histology
  • Systemic and localized argyria have the same features
  • Normal appearing skin under low power
  • Fine black granules in the basement zone of the sweat glands,blood vessel walls, d-e junction, and arrector pili muscles
  • Unstained biopsy section by darkfield illumination demonstrates silver granules outlining basement membrane of the epidermis and the eccrine sweat glands
bismuth
Bismuth
  • Rarely associated with deposition of metallic particles in gums when used IM or orally
  • Also known as the bismuth line
  • Presence of stomatitis or peridontitis increased the risk
  • Generalized cutaneous discoloration, in addition to oral mucous membrane and conjunctival pigmentation resembling argyria has occurred but has not be reported in the last 50 years
slide46
Lead
  • Chronic lead poisoning can produce a “lead hue” with lividity and pallor
  • Deposit of lead in the gums may occur and is known as the “lead line”
slide47
Iron
  • In the past, soluble iron compounds were used in the treatment of allergic contact dermatitides
  • In eroded areas iron was sometimes deposited in the skin, like a tattoo
  • Use of Monsel’s solution can produce similar tattooing
slide48
Gold
  • Chrysiasis may be induced by parenteral administration of gold salts, usually for the treatment of rheumatoid arthritis
  • More commonly recognized in white patients
  • A mauve, blue, or slate/gray pigmentation develops initially on the eyelids, spreading to the face, dorsal hands, and other areas
  • Severity is related to the total dose received, rare < a dose of 20 mg/kg of elemental gold
mercury
Mercury
  • Mercurial pigmentation in the skin is rare, especially since the use of mercurials has been strictly controlled
  • Most common presentation is subcutaneous nodules that result from accidental implantation of elemental mercury from a thermometer into skin
canthaxanthin
Canthaxanthin
  • Orange-red pigment canthaxanthin is present in many plants ( notably algae and mushrooms) and in bacteria. Crustaceans, sea trout, and feathers
  • When ingested for the purpose of simulating a tan, its deposition in the panniculus imparts a golden orange hue to the skin
  • Stools become brick red and the plasma orange, and golden deposits appear in the retina
dye discoloration
Dye Discoloration
  • Blue hands from accidental dyeing were reported by Albert in 1976
  • A man’s hands were dyed as a result of warming them in his armpits while wearing a new blue flannel shirt
  • The dye was insoluble in water, but soluble in sweat
rubeosis
Rubeosis
  • A rosy coloration of the face occurring in young people with uncontrolled diabetes mellitus
  • May be associated with xanthochromia to produce a “peaches and cream” complexion
vitiligo
Vitiligo
  • Usually begins in childhood or young adulthood
  • 50% of cases begin before age 20
  • Prevalence ranges from 0.5% to 1%
  • Females are disproportionately represented among patients seeking medical care
clinical features
Clinical Features
  • An acquired pigmentary anomaly of the skin
  • Manifested by depigmented white patches surrounded by a normal or a hyperpigmented border
  • There may be intermediate tan zones or lesions , halfway between the normal skin color and depigmentaton-so-called trichrome vitiligo
  • Hairs in vitiliginous areas usually become white also
types
Types
  • Localized or focal(including segmental)
  • Generalized
  • Universal
  • Acrofacial
vitiligo56
Vitiligo
  • Generalized is the most common
  • Involvement is symmetrical
  • Most commonly involving the face, upper chest, dorsal aspects of the hands, axillae, and groin
  • Tendency for skin around orifices to be affected (eyes,nose, mouth, ears, nipples, umbilicus, penis, vulva, anus)
  • Lesions also favor areas of trauma (elbows and knees)
generalized vitiligo
Generalized Vitiligo
  • Involvement of perineal and inguinal skin
  • Note the distinct borders
symmetric acral vitiligo
Symmetric, Acral Vitiligo
  • Left: pre-PUVA treatment
  • Right:same pt shows perifollicular pattern of repigmentation during PUVA therapy
segmental vitiligo
Segmental Vitiligo
  • Rapidly progressing segmental vitiligo
segmental vitiligo61
Segmental Vitiligo
  • Segmental vitiligo of the eyebrow and eyelashes
segmental vitiligo62
Segmental Vitiligo
  • Segmental vitiligo on the arm , neck, and chest
  • Note areas of spontaneous follicular repigmentation
  • Left upper back with partial spontaneous repigmentation
slide63
Universal Vitiligo
    • Applies to cases where the entire body surface is depigmented
  • Acrofacial Vitiligo
    • Type affecting the distal fingers and the facial orifices
childhood vitiligo
Childhood Vitiligo
  • Shows an increase in segmental presentation
  • More frequent autoimmune or endocrine anomalies
  • High incidence of premature graying in females
  • Poor response to PUVA therapy
vitiligo65
Vitiligo
  • Completely depigmented oval ivory white areas with convex hyperpigmentated borders
vitiligo66
Vitiligo
  • Vitiligo with depigmentation of the lips
chemical depigmentation
Chemical Depigmentation
  • Chemical depigmentation due to a germicidal detergent
  • Pts usually improve with discontinuation of the offending agent
pathogenesis
Pathogenesis
  • Three possible mechanisms have been proposed as inducing vitiligo
    • Autoimmunity
    • neurohumoral factors
    • autocytotoxicity
  • No mechanism has been conclusively proven
vitiligo69
Vitiligo
  • Histology
    • There is complete loss of melanocytes
    • Usually there is no inflammatory component
  • Differential
    • Morphea
    • Lichen sclerosis
    • Pityriasis alba
    • Tinea versicolor
    • tertiary pinta
treatment
Spontaneous repigmentation occurs in no more than 15% to 25% of cases

Response is slow

PUVA may actually worsen the appearance initially by pigmenting surrounding skin

Cover-up strategies

Fair-skinned pts may manage their disease with sunblock

Sun protection is mandatory in all pts with vitiligo

Topical steroids may be useful on focal or limited lesions

Mid to super high-potency steroids are often required on trunk and acral lesions with the strength tapered as the lesions respond

Treatment
treatment of vitiligo
Treatment of Vitiligo
  • If > 50% of the body surface area is affected by vitiligo, the pt can consider depigmentation
  • This tx is permanent
  • Monobenzone 20% is applied BID for 3-6 months to residual pigmented areas
  • Up to 10 months may be required
  • One in six pts will experience acute dermatitis, usually confined to the still-pigmented areas
vitiligo72
Vitiligo
  • Partial repigmenation of vitiligo following psorralen-ultraviolet light (PUVA) therapy
vitiligo73
Vitiligo
  • Permanent repigmentation after 2 years of photochemotherapy (tripsoralen followed by sunlight exposure)
vogt koyanagi harada syndrome
Vogt-Koyanagi-Harada Syndrome
  • Characterized by bilateral uveitis, symmetrical vitiligo, alopecia, white scalp hair, eyelashes and brows(poliosis, and dysacousia(diminished hearing)
  • Occurs in thirties
  • Initial or meningoencephalitic phase occurs with prodromata of fever, malaise, headache, nausea, and vomiting
  • Also may have psychosis, paraplegia, hemiparesis, aphagia, and nuchal rididity
  • Recovery is usually complete
slide75
VKHS
  • Second phase(ophthalmic-auditory stage) is characterized by uveitis, dreased visual acuity, photopobia, and decreased hearing(50%)
  • The convalescent phase begins 3weeks to 3 months after it begins to improve
alezzandrini s syndrome
Alezzandrini’s Syndrome
  • Extremely rare syndrome characterized by a unilateral degenerative retinits
  • This is followed several months later by ipsilateral vitiligo on the face and ipsilateral poliosis
  • Deafness may also be present
leukoderma
Leukoderma
  • Postinflammatory leukoderma may result from inflammatory dermatoses ie:
    • Pityriasis rosea, psoriasis, herpes zoster, secondary syphilis, and morphea, sarcoidosis, tinea versicolor, mycosis fungoides, scleroderma, and pityriasis lichenoides chronica, and leprosy
  • Other causes: burns, scars, postdermabrasion, and intralesional steroid injections
leukoderma79
Leukoderma
  • Postinflammatory hypopigmentation in a 4-month-old black child with atopic dermatitis
leukoderma80
Leukoderma
  • Postinflammatory hypopigmentation following resolution of guttate psoriasis
pityriasis alba
Pityriasis alba
  • Ill-defined hypopigmented oval patches are generally seen on the face, upper arms, neck, and shoulders of affected persons
  • It can be differentiated from vitiligo by its fine adherent scale, partial hypopigmentation, and distribution
pityriasis alba82
Pityriasis alba
  • White, slightly scaly patches with indistinct borders on a child’s cheek
albinism
Albinism
  • A partial or complete congential absence of pigment in the skin, hair, and eyes (oculocutaneous albinism), or the eyes alone (ocular albinism)
  • Cutaneous phenotype of the various forms is broad, but the ocular phenotype is reasonably constant in most forms
  • The ocular phenotype includes decreased visual acuity, nystagmus, pale irides that transilluminate, hypopigmented fundi, hypoplastic foveae, and lack of stereopsis
albinism85
Albinism
  • This pt has light skin, yellowish white hair, and a lack of pigmentation in nevi
oculocutaneous albinism 1
Oculocutaneous Albinism 1
  • OCA 1 results from mutations in the tyrosinase gene
  • Affected pts are homozygous for the mutant gene or are compound heterozygotes for different mutations in the tyrosinase gene
  • AR
  • Two forms: 1) OCA 1A & OCA 1B (indistinguishable at birth)
  • OCA 1 is most severe with complete absence of tyrosinase activity and complete absence of melanin in the skin and eyes
  • Visual acuity is decreased to 20/400
  • OVA 1B tyrosinase activity is reduced but not absent. Pts may show increase in skin,hair, eye color with age and can tan
oca 1
OCA 1
  • OCA 1B was originally called “yellow mutant” albinism
  • Temperature sensitive OCA (OCA 1-TS) results from mutations in the tyrosinase gene that produce an enzyme with limited activity < 35 degrees C and no activity below this temp. pts have white hair, skin, andeyes at birth, at puberty dark hair develops in cooler acral areas
slide88
Top:albinism with white hair, pale skin, and translucent irides
  • Bottom:ophthalmoscopic view of a pt with albinism demonstrates a pale fundus, poor macular development, and prominent choroidal vasculature
oculocutaneous albinism 2
Oculocutaneous Albinism 2
  • Prevalence of 1:15,000
  • Pts were named “tyrosinase-positive” albinos
  • AR and mutations occur in the P gene
  • P gene codes a membrane transport protein that is present in the melanosome membrane
  • Cutaneous phenotype of OCA 2 pts is broad, ranging from nearly normal pigmentation to virtually no pigmentation
  • Pigmentation increases with age, and visual acuity improves with age
  • Prader-Willi and Angelman syndromes are caused by deletions in the P gene; 1% of pts with these syndromes also have OCA 2
oculocutaneous albinism 3
Oculocutaneous Albinism 3
  • AR-caused by mutations in the tyrosine-related protein 1 (TRP-1), located on chromosome 9
  • OCA 3 has been described only in black pts and is characterized by light brown hair, light brown skin, blue/brown irrides, nystagmus, and decreased visual activity
  • Brown rather than black melanin is formed
ocular albinism
Ocular Albinism
  • There are multiple forms of ocular albinism
  • OA 1 may be present with lighter than expected skin
  • It is X-linked
  • Female carriers have “mud-splattered” fundi
  • Macromelanosomes are found in the skin, so skin bx may be a helpful tool
  • Many cases of AR ocular albinism have been reclassified as OCA 1 or OCA 2
syndromes associated with albinism
Syndromes Associated with Albinism
  • Chediak-Higashsi Syndrome
  • Hermansky-Pudlak Syndrome
  • Griscelli Syndrome(partial albinism with immunodeficiency)
  • Elejalde Syndrome
  • Cross-McKusick-Breen Syndrome
  • Cuna Moon Children
selenium deficiency
Selenium Deficiency
  • Selenium deficiency in the setting of total parental nutrition can lead to pseudoalbinism
  • Skin and hair pigmentation return to normal with supplementation
waardenburg s syndrome
Four genotypic variants exist:

Types 1 & 3 are caused by mutations in the PAX gene on chromosome 2

Type 2 is caused by mutations in the MITF gene on chromosome 3, and type 4 due to mutations in the ENDRB gene on chromosome 13

Pts have features of piebaldism, with white forelock, hypopigmentation, premature graying, synophrys, congenital deafness, a broad nasal root, and ocular changes including heterochromia irides

Apparently, melanoblasts fail to reach the target sites during embryogenesis

Waardenburg’s Syndrome
piebaldism
Piebaldism
  • Rare, AD with variable phenotype, presenting at birth
  • White forelock, patchy absence of skin pigmenation
  • Depigmented lesions are static and occur on the anterior and posteroir trunk, mid upper arm to wrist, mid-thigh to mid-calf, and shins
  • A characteristic feature is the presence of hyperpigmented macules within the areas of lack of pigmentation and on normal skin
piebaldism98
Piebaldism
  • Segmental white patch on the neck with a tuft of white hair present from birth
piebaldism99
Piebaldism
  • White forelock and patch of unpigmented skin in a young girl with piebaldism
piebladism
Piebladism
  • The white forelock arises from a triangular or diamond-shaped midline white macule on the frontal scalp or forehead
  • The medial portions of the eyebrows, and eyelashes may be white
  • Histologically, melanocytes are completely absent in the white macules
  • Etiology is a mutation in the c-kit protooncogene
  • Phenotypic differences seen in families is caused by different locations of mutations in the gene
  • The white lesions may respond to surgical excision
idiopathic guttate hypomelanosis
Idiopathic Guttate Hypomelanosis
  • AKA leukopathica symmetrica progressiva
  • Very common aquired disorder affecting women more frequently than men
  • Usually occurs after age 40
  • Lesions occur on the shins and forearms; are small (6 or 8mm), rarely become very numerous ( a dozen or two at most), and never occur on the face or trunk
  • Lesions are irregularly shaped and very sharply defined, like depigmented ephelides, and are only of cosmetic significance