DISORDERS OF PIGMENTATION

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pigmentation, disorders, vitiligo, hyperpigmentation, hypopigmenattion, melanin

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DISORDERS of Pigmentation:

Dr. Angelo Smith M.D WHPL DISORDERS of Pigmentation

Skin color:

Skin color Determined by - melanin - haemoglobin - carotenoids Melanin - major determinant Melanin is synthesized by melanocytes within melanosomes and transferred to keratinocytes Constitutive skin colour - genetically determined Facultative skin colour - induced by sun and hormones

An Overview:

An Overview Skin pigmentation has far-reaching social and psychological implications White people strive for tanning which while brown and black people strive for a lighter skin Melanin pigmentation disorders are important for medical and cosmetic reasons

PowerPoint Presentation:

Human beings come in a glorious spectrum of different colors: light, dark, plain or freckly skin; black, brunette, blond, auburn, and white hair; and eyes that are blue, hazel, green, amber and brown, to name just a few. It’s amazing to realize that most of this color is attributed to a single class of pigments : the melanins .

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 Variations in skin color is related to the number of melanosomes , the degree of melanization , and the distribution of the epidermal melanin unit

Melanin:

Melanin Two types - eumelanin (black or brown) - pheomelanin (reddish) Derived from tyrosine Tyrosine Tyrosinase DOPA[3,4 dihydroxy phenylalanine] Dopaquinone Dopachrome 5, 6 dihydroxindole Eumelanin Cysteinyldopa pheomelanin

Normal Pigmentation:

Normal Pigmentation Normal skin pigmentation is influenced by: -the degree of vascularity -the amount & location of melanin -the presence of carotene -the thickness of the horny layer

Melanin Production:

Melanin Production The amount produced is dependent on: -genetics -the amount and the wavelengths of ultraviolet light received -the amount of melanocyte-stimulating hormone (MSH) secreted - the effect of melanoccyte stimulatingg chemicals like furocoumarins ( psoralens )

Approach to a patient:

Approach to a patient History Onset : birth, infancy or later Cause: sun exposure, drugs, occupation Systemic complaints Family history: neurofibromatosis, tuberous sclerosis, vitiligo

PowerPoint Presentation:

Examination: Type of lesion : brown, blue, hypopigmented (check sensation), depigmented Shape : Ash leaf macules (tuberous slerosis ) Koebner phenomenon( vitiligo ) Distribution pattern : linear/segmental (nevus depigmentosus ), symmetric (vitiligo), specific sites ( melasma , Addison’s disease)

PowerPoint Presentation:

Examination aids: Hand lens Oblique lighting for elevation or depression Dermatoscopy Wood’s lamp - 360 nm. Epidermal pigmentary anomalies made more prominent Histology- H and E for presence or absence of melanin Dopa reaction - melanocytes stain dark Silver stains - melanin stains black

CLASSIFICATION:

CLASSIFICATION GENERALIZED LOCALISED HYPERPIGMENTATION HYPOPIGMENTATION DEPIGMENTATION CONGENITAL ACQUIRED

hypopigmentation:

hypopigmentation

Classification:

Classification Genetic and Developmental: Albinism , Nevus depigmentosus , Nevus anaemicus , Halo nevus, Tuberous sclerosis (ash leaf macule) Endocrine: Addison’s disease, Hypothyroidism, Hypopituitarism Nutritional: Vit.B12 deficiency, Kwashiorkor , Malabsorption

PowerPoint Presentation:

Post-inflammatory: Pityriasis alba , Eczema, Psoriasis, Pityriasis rosea , Lupus erythematosus, Morphea , Scleroderma, Bullous dermatoses Infection: Leprosy, Tinea versicolor , Candidiasis, Post kala azar dermal leishmaniasis Chemicals and Drugs: Phenols, Arsenicals, Hydroquinone, Steroids

PowerPoint Presentation:

Physical: Burns, Trauma, Post dermabrasion, Post laser Miscellaneous: Idiopathic guttate hypomelanosis , Vitiligo , Mycosis fungoides

Albinism:

Albinism Oculocutaneous albinism involves skin, hair and eyes or the eyes alone (ocular albinism) Mostly autosomal recessive Absence of pigmentation from birth Photophobia, reduced visual activity, nystagmus , pale irides that transilluminate , hypopigmented fundi, hypoplastic foveae, and lack of stereopsis Sunburns, skin cancers common Protection of eyes and skin by sunglasses, sunscreens SPF > 20, clothing

PowerPoint Presentation:

Top: albinism with white hair, pale skin, and translucent irides Bottom: ophthalmoscopic view of a patient with albinism demonstrates a pale fundus, poor macular development, and prominent choroidal vasculature

Piebaldism:

Piebaldism Rare, AD with variable phenotype, presenting at birth White forelock , patchy absence of skin pigmentation Depigmented lesions are static and occur on the anterior and posterior trunk, mid upper arm to wrist, mid-thigh to mid-calf, and shins A characteristic feature is the presence of hyper pigmented macules within the areas of lack of pigmentation and on normal skin

PowerPoint Presentation:

White forelock and patch of unpigmented skin in a young girl with piebaldism

PowerPoint Presentation:

Segmental white patch on the neck with a tuft of white hair present from birth

Waardenburg’s syndrome:

Waardenburg’s syndrome Rare, autosomal dominant disorder White forelock Hypertelorism Congenital deafness Hypomelanotic macules Heterochromic irides Incomplete forms may occur

Tuberous sclerosis:

Tuberous sclerosis Autosominal dominant, neurocutaneous syndrome with skin lesions, mental retardation and epilepsy Skin lesions are ash-leaf macules , angiofibromas and shagreen patches Ash-leaf macules - present at birth in > 90% cases, so important in early diagnosis Oval or ash-leaf shaped, hypopigmented macules, made prominent in Wood’s lamp Long axis is axial on limbs and transverse on trunk

Nevus depigmentosus:

Nevus depigmentosus A hypo pigmented birthmark which is congenital and stable Irregular, geographic margins and quasidermatomal distribution Block in transfer of melanosomes from melanocytes to keratinocytes Sporadic occurrence, no medical significance and no treatment required

Kwashiorkor:

Kwashiorkor Protein deficiency in post weaning years Reddish patches which turn into dark plaques which turn white after exfoliation (crazy pavement dermatosis) Disruption of melanogenesis is due to multiple deficiencies Pigment changes and dyschromic hair are reversible with proper diet

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 intralesioal steroid injections

PowerPoint Presentation:

Post inflammatory hypopigmentation in a 4-month-old black child with atopic dermatitis

PowerPoint Presentation:

Post inflammatory hypopigmentation following resolution of guttate psoriasis

Tinea versicolor:

Tinea versicolor Common, superficial fungal infection Overgrowth of Malasezzia furfur - a normal resident Common after puberty; face, neck, upper trunk affected Nonpruritic or mildly pruritic, hypo or hyperpigmented lesions with fine scales Common in tropics; during summers

Leprosy:

Leprosy Both hypo pigmented and erythematous lesions common Hypo pigmented macules common in tuberculoid type of disease Each hypo pigmented lesions in leprosy endemic areas should be examined for sensations of touch, pain, temperature Treatment according to type of leprosy

Pityriasis alba:

Pityriasis alba A common disorder in children Hypo pigmented lesions with powdery scaling; chiefly affecting face Etiology not known but may be a feature of atopy or malnutrition To be differentiated from indeterminate leprosy and early vitiligo Treatment with emollients

PowerPoint Presentation:

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

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

Vitiligo:

Vitiligo Usually begins in childhood or young adulthood An acquired Pigmentary anomaly of the skin Manifested by depigmented white patches surrounded by a normal or a hyper pigmented border There may be intermediate tan zones or lesions , halfway between the normal skin color and depigmentation – so - called trichrome vitiligo Hairs in vitiliginous areas usually become white also Rarely, the patches may have a red, inflammatory border Patches are of various sizes and configurations

Types:

Types Localized or focal (including segmental) Generalized Universal Acrofacial

Vitiligo:

Vitiligo Local loss of pigment may occur around nevi and melanomas, the so-called halo phenomenon Vitiligo-like leukoderma occurs in 1% of melanoma patients In those previously dx with melanoma, it suggests metastatic disease Paradoxically, patients who develop leukoderma have a better prognosis than patients without it Halo nevi are more common in patients with vitiligo Lesions are hypersensitive to UV light and burn easily when exposed to the sun

HennA Induced Vitiligo:

HennA Induced Vitiligo

Chemical Depigmentation:

Chemical Depigmentation Chemical depigmentation due to a germicidal detergent Pts usually improve with discontinuation of the offending agent

Hyperpigmentation:

Hyperpigmentation

Disorders of hyperpigmentation:

Disorders of hyperpigmentation May be epidermal or dermal Epidermal hyperpigmentation due to - Increased melanin with normal number of melanocytes - Increased number of melanocytes Dermal hyperpigmentation due to - Melanin from epidermis transferred to dermis - Melanin formed in dermal melanocytes - Melanin pigments appears blue-gray due to Tyndall effect

Classification – EPIDERMAL:

Classification – EPIDERMAL Physiologic: Pigmentary demarcation lines , sun tanning Genetic and Developmental: Lentigines, Freckles , Peutz-Jeghers syndrome, Melanocytic nevus, Café-au- lait spots , Xeroderma pigmentosum , Becker’s nevus , Nevus spilus , Acanthosis nigricans

PowerPoint Presentation:

Post-inflammatory: Eczema, Psoriasis, Lichen planus, Lupus erythematosus, Scleroderma, Morphoea , Vagabond’s disease Infection: Tinea versicolor , Tinea nigra Nutritional: Kwashiorkor, Pellagra, Vit.B12, Vit.C , Folic acid deficiency

PowerPoint Presentation:

Physical: Trauma, Radiation dermatitis Endocrine: Melasma , Addison’s disease , Cushing’s syndrome, Phaeochromocytoma , Acromegaly, Hyperthyroidism Neoplastic: Malignant melanoma, Seborrhoeic keratosis, Pigmented basal cell carcinoma

PowerPoint Presentation:

Genetic and Developmental: Mongolian spots, Nevus of Ota/Ito , Incontinentia pigmenti Inflammatory: Stasis dermatitis, Post inflammatory to eczema and fixed drug eruption Chemicals and Drugs: Anti- malarials , OC Pills, Minocycline, Clofazimine , Topical hydroquinone, Tattoos DERMAL PIGMENTATION

PowerPoint Presentation:

Endocrine: Melasma Physical: Thermal burns, Post traumatic Infection: Syphilis, Yaws, Pinta Neoplastic: Metastasis of melanoma

PowerPoint Presentation:

Nutritional: Chronic nutritional deficiency Metabolic: Hemochromatosis , Alkaptonuria , Macular / Lichen amyloidosis Miscellaneous: Pigmented purpuric dermatosis, Purpura

PDL:

PDL Pigmentary demarcation lines (PDL) were first described by Matzumoto on the upper and lower limbs of Japanese people in 1913 Also known as Futcher’s or Voight’s lines Pigmentary demarcation lines are borders of abrupt transition between more deeply pigmented skin and that of lighter pigmentation They do not correspond to Blaschko’s lines or dermatomal lines but to voigt ’ lines Considered by some to be a variant of normal pigmentation

PowerPoint Presentation:

Can be divided into five categories: Group A - lines along the outer upper arms with variable extension across the chest Group B - lines along the posteromedial aspect of the lower limb 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

PowerPoint Presentation:

More than 70% of blacks have one or more lines These are much less common in whites Type B lines often appear for the first time during pregnancy

Melanocytic nevi:

Melanocytic nevi Benign proliferations of melanocytic nevus cells at the dermo -epidermal junction May be congenital or acquired Acquired nevi are more common Appear in infancy or childhood, slowly grow and mature and then regress in older life Important for cosmetic reasons and as precursors for melanoma ( esp in white)

Acquired nevi:

Acquired nevi Round or oval, uniformly coloured and sharply bordered lesions Appear after birth Increase in frequency during childhood and adolescence and plateaus during middle age Most of them start as junctional nevi which are flat and histologically confined to dermal-epidermal junction

Acquired nevi:

Acquired nevi Gradually mature to compound nevi which have nests and columns of nevus cells in dermis along with the junctional component. These are raised, rounded, brown or black Intradermal nevi : Compound nevi mature to intradermal nevi with nevus cells only in dermis having neuron like appearance. These are dome shaped, nonpigmented and may have one or more coarse hairs

Congenital melanocytic nevi:

Congenital melanocytic nevi Small < 1.5 Intermediate: 1.5 to 20 cms Giant > 20 cms Malignant potential for giant nevi is 4-6% Excision justified for cosmetic reasons and risk of malignancy

Café au lait macules (CALM):

Café au lait macules (CALM ) Circumscribed, brown macules with irregular margins, 2-5 cm in size Present at birth Isolated CALM may occur in 10-20% of normal population No increase in the number of melanocytes Five or more CALM of size >0.5 cm in prepubertal age group and >1.5 cm in an adult are strongly suggestive of neurofibromatosis

Becker’s nevus:

Becker’s nevus Acquired, pigmented, hairy plaque common on trunk, more common in males Appears in first or second decade Common sites: shoulder, chest, back May become verrucous with hair growth and then remains stable No treatment needed

Ephelides (Freckles):

Ephelides ( Freckles ) Tiny (<0.5 cm), discrete brown macules Common in fair skinned Appear in childhood on sun exposed parts; lighten in absence of sun exposure Melanocytes are not increased in number but are hyperactive May be part of some syndromes

Melasma:

Melasma A common macular brown coloured lesion seen on face in males and females 90% (darker skin) Common in pregnancy: Mask of pregnancy (clears in few months) Etiology: hormones (OC Pills) (remains for yrs after stoppage) and sunlight May disappear or remain after delivery Forehead, nose, cheeks affected. The three clinical patterns are: centrofacial , malar, mandibular Exacerbation on sun exposure Histologically may be epidermal, dermal or mixed

Post-inflammatory hyperpigmentation:

Post- inflammatory hyperpigmentation After resolution of specific eruptions Common after lichen planus, atopic dermatitis, acne vulgaris, contact dermatitis, psoriasis, pyodermas etc. Discrete macules exactly on the sites previously affected by eruptions May persist for months

Fixed Drug Eruption (FDE):

Fixed Drug Eruption (FDE) NSAIDs, antibiotics, barbiturates etc. Reddish brown macule → edematous → desquamation → pigmentation Recurs at same site on rechallenge May become generalised or blistering Melanin is increased in epidermis and dermis ( melanophages )

Mongolian spots:

Mongolian spots Common in Asian newborns on buttocks or lower back Due to arrest of migrating melanocytes in the dermis No treatment is needed as they spontaneously disappear by 2 to 10 yrs of age

Nevus of Ota and Ito:

Nevus of Ota and Ito Nevus of Ota (around eyes) and nevus of Ito (shoulder area) are other examples of dermal pigmentation

Peutz-Jeghers:

Characterized by 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 Macules may also occur around the mouth, on the central face, backs of the hands, especially the fingers, and on the toes and tops of the feet. Associated polyposis involves the small intestine 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

PowerPoint Presentation:

Incidence of malignancy within the polyps is 2-3% Incidence of GI malignancy is low, but increased incidence of other kinds of cancer - breast, and gynecologic malignancies in women. Syndrome is inherited and transmitted as a simple mendelian dominant trait

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 Diabetes produces diffuse bronzing of the skin Patients with virilizing adrenal tumors usually develop hyperpigmentation and hypertrichosis

ADDISONS DISEASE:

ADDISONS DISEASE diffuse melanosis pronounced in the axillae and palmar creases, and nipples and genitals, and buccal mucosa

PowerPoint Presentation:

Diffuse skin hyperpigmentation, increased pigmentation of the palmar creases and wrists compared to a normal female control (far right), her hyperpigmentation resolved

Hemosiderin Hyperpigmnetation:

Hemosiderin Hyperpigmnetation Pigmentation due to deposits of hemosiderin occurs in: -purpura -hemochromatosis -hemorrhagic diseases -stasis ulcers

Hemochromatosis:

Characterized by: Gray-brown mucocutaneous hyperpigmentation Diabetes mellitus Hepatomegaly Usually are present: Cirrhoisis Hypogonadism Liver cirrhosis Hemochromatosis

PowerPoint Presentation:

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

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 Examples: conjunctivae, from eye drops; a wound from sulfadiazine cream, earlobes from silver earings ; and from silver acupuncture needles Can also occur from occupational exposure, usually silversmiths In localized exposures, the appearance may be separated by many years from the exposure Argyria

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

Lead:

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”

Gold:

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 Pigment is accentuated in light-exposed areas, and sun protected areas do not demonstrate 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

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