M
Macrocystic lymphangioma
Etiology:
Description: cysts more than 2 cm
Mal de Meleda
Etiology:
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Appearance: glove + stocking malodorous keratoderma, more erythematous
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Inheritance: AR
Male Pattern Hair Loss
Etiology: increased sensitivity of androgen receptors in hair follicles to DHT
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Location: frontal hairline, crown
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Tx: topical minoxidil, oral finasteride or dutasteride
Marjolin Ulcer
Etiology:
Cause: rare development of cutaneous SCC in the site of a scar or ulcer; most commonly forms at the site of an old thermal burn scar
Description: non-healing sore that steadily increases in size, has excessive granulation tissue, foul-smelling pus, and bleed easily on contact
Mastocytosis
Etiology:
Cause: Gain of function mutation in KIT gene = growth of mast cells = more histamine release
Description: small reddish-brown spots or bumps (urticaria pigmentosa)
Melanoma
Etiology:
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Screening post dx:
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q3 mo for 1st year
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q6 mo for up to 5th year
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q1 yr after 5 years
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Dermoscopy: blue/white veil, dark globules, peripheral globules, negative pigment network, pseudopods, radial streaming
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Cause: excessive UV light exposure (sunlight, tanning beds), BRAF kinase V600E mutation
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Description: mole that is asymmetrical, irregular border, color variation, diameter >6 mm, and evolving over time
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Locations:
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Most typical: areas exposed to sun: back legs arms face. Darker skin: soles of feet palms of hands fingernail beds
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At risk: fair skin, hx of sunburn, many moles or unusual moles, family hx of melanoma, immunosuppressed
Merkel Cell Carcinoma
Etiology:
Cause: ultraviolet light exposure
Description: pearly pimple-like lump, sometimes skin-colored, red, purple or bluish-red, though they are rarely tender to the touch
At risk: older, fair skin, male gender, immunosuppressed
Milaria Rubra / Heat Rash
Etiology:
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Appearance: small, erythematous blister-like papules
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Etiology: sweat ducts become blocked, trapping sweat under skin, leading to inflammation
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At risk: hot, humid environments
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Location: skin folds, neck, chest, back
Milia
Etiology:
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Appearance: 1-2 mm white to yellow subepidermal papules
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Location: cheeks, eyelids, forehead, genitalia
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Tx: nick surface + express
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Cause: small cyst containing keratin
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Description: tiny pearly-white bumps just under the surface of the skin
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Locations: face, especially eyelids + cheeks
Molluscum contagiosum
Etiology:
Cause: Molluscum contagiosum
Description: umbilicated flesh-colored papules
Location: mostly arise in warm moist places (armpit, behind the knees, groin or genital areas); do not occur on palms or soles
At risk: children and immunocompromised adults
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Boat sign
Mpox / Monkeypox
Etiology:
Cause: Orthopoxvirus
Description:
1. first 5 days of the infection, patients experience 'flu-like' symptoms
2. rash similar to that seen in chickenpox develops
3. maculopapules,evolve into vesicles, pseudpustules, crusting over, andn atrophic scars and lasts for around 10 days
Location: Lesions predominate on the face but may develop on the palms, soles, and dorsal hands and feet
At risk: MSM, endemic to Africa
Mucocutaneous Candidiasis
Etiology:
Cause: Candida albicans > other Candida species
Description: pruritic, well-demarcated, erythematous patches
Location: intertriginous areas (axillae, grown, in between toes, beneath breasts)
Associated with: onychomycosis
Mycosis Fungoides
Etiology:
Cause: unknown; triggers proliferation of cerebriform T cells
Description:
Patch stage = flat erythematous scaling with well-defined borders in non-sun-exposed areas or hypopigmented lesions on darker skinned individuals
Plaque stage = pruritic raised borders with irregular contours and reddish-brown in color
Tumor stage = exophytic violaceous lesion
Myofibroma
Etiology:
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Histo: hypocellular pink blue nodules with dilated branching staghorn vessels and cellular areas
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At risk: babies/kids
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Types:
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Single – MC, skin/SQ nodule
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Muliptle
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Generalized
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