Pigmented & common skin disorders Flashcards
Define albinism and the increased risk
Normal melanocyte number with decreased melanin production due to decreased tyrosinase activity/defective tyrosine transport
Increased risk of skin cancer
Define melasma and who its found in
Acquired hyperpigmentation associated with pregnancy (“mask of pregnancy”) or OCP use
More common in patients with darker skin tones
Define vitiligo and its association
Irregular patches of complete depigmentation. Caused by destruction of melanocytes (believed to be autoimmune)
Associated with other autoimmune disorders
Define Waardenburg syndrome
Patchy depigmentation of skin, hair, and irises that can be associated with deafness
Caused by defects in the differentiation of neural crest cells into melanocytes
Define seborrheic dermatitis
Erythematous, well-demarcated plaques with greasy yellow scales in areas rich in sebaceous glands, such as scalp, face, and periocular region
Sebaceous glands are not inflamed but play a role in disease development
Possibly associated with Malassezia spp
Epidemiology of seborrheic dermatits
Common in both infants (cradle cap) and adults, associated with Parkinson disease
Tx of seborrheic dermatitis
Topical antifungals and glucocorticoids
Define acne + causes
Multifactorial etiology
Increased sebum/androgen production, abnormal keratinocyte desquamation
Cutibacterium acnes colonization of the pilosebaceous unit (comedones), and inflammation (papules/pustules, nodules, cysts)
Define atopic dermatitis (eczema)
Type I hypersensitivity reaction
Pruritic eruption, commonly on skin flexures
Associations of eczema
Other atopic diseases (asthma, allergic rhinitis, food allergies)
Lab findings & mutations in eczema
Increased serum IgE
Mutations in filaggrin gene predispose (via skin barrier dysfunction)
Where does eczema appear on the body
Often appears on face in infancy and then in antecubital fossa in children and adults
Define allergic contact dermatitis
Type IV hypersensitivity reaction secondary to contact allergen (eg, nickel, poison ivy, neomycin)
Define melanocytic nevus
Common mole
Benign, but melanoma can arise in congenital or atypical moles
Intradermal nevi are papular
Junctional nevi are flat macules
Define pseudofolliculitis barbae and location
Foreign body inflammatory facial skin disorder characterized by firm, hyperpigmented papules and pustules that are painful and pruritic
Located on cheeks, jawline, and neck
Commonly occurs as a result of shaving (“razor bumps”), primarily affects Black males
Define psoriasis
Papules and plaques with silvery scaling especially on knees and elbows
Name the findings in psoriasis
Acanthosis with parakeratotic scaling (nuclei still in stratum corneum), Munro microabscesses
Increased stratum spinosum, decreased stratum granulosum
Clinical findings + associations in psoriasis
Auspitz sign: pinpoint bleeding spots from exposure of dermal papillae when scales are scraped off
Associated with nail pitting and psoriatic arthritis
Define rosacea
Inflammatory facial skin disorder characterized by erythematous papules and pustules but no comedones
Associations + complications of rosacea
May be associated with facial flushing in response to external stimuli (eg, alcohol, heat)
Complications include ocular involvement, rhinophyma (bulbous deformation of nose)
Define seborrheic keratosis
Flat, greasy, pigmented squamous epithelial proliferation of immature keratinocytes with keratin-filled cysts (horn cysts)
Lesions occur on head, trunk, and extremities
Common benign neoplasm of older persons
Clinical sign of seborrheic keratosis
Leser-Trélat sign: rapid onset of multiple seborrheic keratoses, indicates possible malignancy (eg, GI adenocarcinoma)
Define verrucae
Warts; caused by low-risk HPV strains
Soft, tan-coloured, cauliflowerlike papules
Epidermal hyperplasia, hyperkeratosis, koilocytosis
Condyloma acuminatum on anus or genitals
