Ch 24: Skin: BM, Vascular, Acne Flashcards
Heterogeneous group of disorders loosely bound by their hereditary nature which form blisters at sites of minor trauma and are usually noted at birth or shortly after
epidermolysis bullosa (EB)
Group of autosomal recessive and autosomal dominant EB attributed to cytokeratin intermediate filament gene mutations which involve cytolysis of basal keratinocytes and healing without scar formation
Epidermolytic EB (EB simplex)
Characteristics of blisters formed in epidermolytic EB
Intraepidermal vesicles with a roof of nearly intact epidermis and floor of fragmented basal keratinocytes
Group of autosomal recessive EB which form blisters within lamina lucida. Healing occurs without scarring, but may include residual atrophy
Junctional EB
Type of junctional EB associated with mutations in genes for laminin and integrin isoforms
Severe junctional EB
Type of junctional EB associated with mutations in the gene for type XVII collagen
Benign junctional EB
Characteristics of blisters formed in junctional EB
Intraepidermal vesicles with a roof of intact epidermis and floor of intact lamina densa
Group of autosomal recessive and autosomal dominant EB attributed to defects in anchoring fibrils (type VII collagen) where blisters are deep to the lamina densa and healing involves atrophic scarring
Dermolytic (dystrophic) EB
Characteristics of blisters formed in dermolytic (dystrophic) EB
Subepidermal vesciles with a roof of normal epidermis an intact lamina lucida and lamina densa and floor of outer papillary dermis
Type of autosomal recessive EB attributed to mutation in FERMT1 gene encoding for the adhesion protein, kindling-1
Kindler syndrome
Kindler syndrome is set apart from other inherited EBs by clinical presentation of
Mottled skin pigmentation (poikiloderma) and photosensitivity
Subepidermal, autoimmune blistering disease where complement-fixing IgG targets basement membrane proteins, BPAG1 and BPAG2
Bullous Pemphigoid (BP)
Complement proteins which promote degranulation of mast cells in Bullous Pemphigoid
Anaphylatoxins C3a and C5a
Ultimate cause of disruption of anchoring filaments, breakdown of lamina densa, and vesicle formation at the lamina lucida following release of chemotactic factors (IL-5 & Eotaxin) by mast cells
Eosinophilic degranulation at the dermal-epidermal junction
Characteristics of blisters formed in Bullos Pemphigoid
Subepidermal blister with a roof of intact epidermis and floor of lamina densa
Blister contains eosinophils, lymphocytes, neutrophils, and fibrin
Treatment typically used to shorten course of Bullous Pemphigoid
Systemic administration of corticosteroid
Intensely pruritic cutaneous eruptions with small subepidermal vesicles associated with gluten sensitivity and IgA complex deposition at the dermal papillae
Dermatitis Herpetiformis
Immune cells typically seen at the tips of dermal papillae in response to IgA deposition in dermatitis herpetiformis
Neutrophils
Acute, self-limited disorder ranging from formation of erthematous macules and blisters to ulcers which are usually a reaction to a drug or infectious agent such as herpes simplex
Erythema multiforme
An unusually severe, and frequently fatal, form or erythema multifome involving mucosal surfaces and internal organs
Stevens-Johnson syndrome
Autoimmune disorder associated with epidermal injury due to exogenous agents, such as UV light, which typically presents with malar or butterfly rash, immune complexes in the basement membrane zone, and elevated antinuclear antibodies (ANA)
Acute systemic lupus erythematosus
Cell mediated immunologic reaction to epidermal injury resulting in saw-tooth appearing inflammation
Lichen Planus
In lichen planus, what characteristically appears at the dermal-epidermal junction
band-like congregation of lymphocytes
Lichen Planus is associated with which viral infection
Hepatitis C
Basal cell layer destruction and subsequent reactive epidermal proliferation in Lichen Planus leads to what characterization in each epidermal layer
Stratum corneum: Hyperkeratosis without parakeratosis
Stratum granulosum: thickened in an often wedge-shaped pattern
Stratum spinosum: variably thickened
Stratum basale: cuboidal keratinocytes replaced by flattened or polygonal keratinocytes
Clinical features of Lichen Planus include
Violet colored (violaceious), flat-topped papules and Wickham striae
Lichen planus typically affects
flexor surfaces and wrists
Oral mucous membrane involvement in Lichen Planus manifests as
Wickhamm striae
IgE-dependent hypersensitivity reaction with degranulization of mast cells involving edema of the superficial dermis
Urticaria (hives)
With urticaria, within few hours of offending agent, what skin lesions appear
Pruritic papules and plaques
IgE-dependent hypersensitivity reaction, with degranulization of mast cells, involving egg-like swelling from edema in the deeper dermis or subcutis
Angioedema
Heritable angioedema is associated with mutation in
C1-esterase inhibitor
Both Urticaria and Angioedema are treated with
Antihistamines
Exaggerated IgE-dependent response which allows you to write on your skin and form hives in the shape of legible words
Dermatographism
Immune reaction which presents as palpable purpura that doesn’t blanche under pressure
Cutaneous necrotizing vasculitis (CNV)
CNV is typically due to neutrophil degranulation and vessel damage following
Immune complex deposition on vessel walls
Cutaneous necrotizing vasculitis is also known as
hypersensitivity angiitis
The cases of CNV which are not of unknown etiology or related to a chronic disease are often associated with
An infectious agent (ex: Hep B virus, Streptococcus)
Three main characteristics of vascular damage in CNV are
Extravasation of erthryocytes
Fibrin deposition
Leukocytoclasia
Cell-mediated hypersensitivity to allergens which involves epidermal edema and a pruritic, erythematous, exudative rash
Allergic contact dermatitis
Allergic contact dermatitis is a model of
Spongiotic dermatitis
Which phase of allergic contact dermatitis involves migration of Langerhans cells into dermal lymphatics and subsequent presentation to CD4+ T cells
Sensitization phase
Which phase of allergic contact dermatitis involves epidermal entry of sensitized CD4 T cells and release of cytokines after re-exposure to allergen
Elicitation phase
Three common allergens for contact dermatitis include
Hapten containing plants (ex: poison ivy)
Irritant chemicals (ex: detergents)
Drugs (ex: penicillin)
General term referring to cell-mediated immune response to indigestible antigens in the epithelium
<p>Granulomatous dermatitis </p>
Multiorgan systemic disorder of unknown etiology whose skin lesions present as noncaseating granulomas in the reticular dermis
Sarcoidosi
Benign, self-limited disorder characterized by necrobiosis, or focal collagen degeneration, surrounded by palisaded macrophages
Granuloma annulare
Areas typically affected by granuloma annulare
Dorsum of the hands and feet
Disorder of the reticular dermal connective tissue marked by fibrosis and tightening of the skin
Scleroderma
Important clinical feature of early scleroderm
Raynaud phenonmenon or non pitting edema of hands or fingers
Involvement of the esophagus in scleroderma can lead to
Dysphagia
Disorder similar to sceleroderma, but only involving patchy, circumscribed areas of skin
Morphea
Heterogenous group of diseases characterized by inflammation of subcutaneous tissue
Panniculitis
Cutaneous disorder with self-limited, nonsuppurative, tender nodules over extensor surfaces of lower extremities
Erythema nodusum
Histologically, erythema nodosum is characterized by
Necrosis and fibrosis of adipose tissue
Neutrophilic inflammation
Foreign body giant cells
Inflammatory cells
Disorder of chronic, recurrent subcutaneous nodules of plaques on the legs associated with mycobacterium tuberculosis
Erythema induratum
Self-limited inflammatory disorder of sebaceous follicles resulting in papular or pustrular lesions
Acne vulgaris
Excess keratin production at the neck of follicles and hormone associated increases in sebum production forms
Comedones (plugged follicles)
What are the two types of comedones
Blackheads (open comedones)
Whiteheads (closed comedones)
Anaerobic diphtheroid associated with acne vulgaris which releases hydrolytic enzymes and forms pustules or follicular abscesses
Propionibacterium acnes
