Fitz9. Part 3. Dermatitis Flashcards
Case: multiple pruritic erythematous papulovesicles with pinpoint crusting or frank weeping on flexures and extremities
- Disease?
- primary manifestation in adults?
- hallmark symptom of disease?
- ATOPIC DERMATITIS
- chronic hand eczema
- pruritus
Major criteria of atopic dermatitis
pruritus,
eczematous dermatitis: face extensors infant, flexures adult
chronic relapsing disease,
personal or family history
most common complication in atopic dermatitis:
- Bacterial:
- viral:
- fungal:
- Bacterial: superficial staph aureus
- viral: eczema herpeticum
- fungal: Malassezia sympodialis
(2) pathways responsible for atopic dermatitis
- epidermal dysfunction
2. altered/ innate or adaptive immune response
decrease in skin barrier function of atopic dermatitis due to inc/dec of:
- cornified envelopes
- ceramide
- proteolytic enzymes
- TEWL
- Dec cornified envelopes
- Dec ceramide
- Inc proteolytic enzymes
- Inc TEWL
Mutations seen in atopic dermatitis
- loss of function mutations
- gain of function mutations
- loss of function: filaggrin
2. gain of function:IL4, IL13
the only FDA approved systemic drug for atopic dermatitis that targets IL4 and IL13
Dupilumab
Syndromes with atopic dermatitis are ___ with ___ mutations
- Netherton (SPINK5)
2. NISCH (Claudin 1)
key cytokines in atopic dermatitis (2)
TSLP, IL33
chemokines in atopic dermatitis
fractalkine, IFNy-10, monokine CC chemokines, eotaxin, RANTES
most potent cytokines downregulating filaggrin in atopic dermatitis (3)
TSLP, IL4 and IL13
IL___ that causes pruritus in atopic dermatitis
IL31
Histopathologic difference between acute versus chronic atopic dermatitis
Acute: spongiosis, inc memory T cells, DEgranulating mast cells
Chronic: elongated rete ridges, inc IgE, macrophages in dermis, granulated mast cell, eosinophils
cornerstone treatment of mild atopic dermatitis
emollients
FDA drug for younger children with atopic dermatitis (3)
Desonide, fluocinolone, fluticasone
Case: well-demarcated coin-shaped plaques form from coalescing papules and papulovesicles. Often studded or satellite papulovesicles appear at periphery with crust at the entire surface with normal surrounding skin.
- Disease?
- Commonly assoc with? (5)
- Commonly assoc infection?
- Due to what drugs? (7)
- Mainstay treatment?
- NUMMULAR ECZEMA
- atopic dermatitis, xerosis, ICD, ACD, candida
- Staph infection: odontogenic/ dental
- Isotretinoin, IFN a-2b, infliximab, gold, ribavirin, amalgam, mercury
- topical corticosteroids
Case: lichenified dry and scaly plaques with excoriations on the scalp, name, angles, extensors. May have hyperlinear palms
- Disease?
- associated with what disease?
- histopath?
- LICHEN SIMPLEX CHRONICUS
- Atopic dermatitis (dennie morgan fold, hyperlinear palms)
- thickened papillary dermal collagen with vertical streaks
Case: Hyperkeratotic firm hard nodules with overlying excoriation. May see sparing of the upper back or butterfly sign.
- Disease
- Pathogenesis
- hallmark of disease
- what is this disease called if it is associated with atopic dermatitis?
- histopath and stain?
- PRURIGO NODULARIS
- Increase CGRP (calcitonin), substance P, nerve growth factor, TNFa, IL1, IL8, TRPV
- itch
- besnier prurigo
- thick epidermal collagen with neural hypertrophy. S100.
Case: pruritic eczematous dermatitis initially localized to the primary site of allergen exposure
- Disease?
- key components of the history as clues to allergy?
- key symptom for this disease?
- diagnostic test of choice
- mainstay tx
- first line tx.
- ALLERGIC CONTACT DERMATITIS
- itch and swelling
- pruritus
- patch testing
- avoidance
- topical corticosteroids
ACD is what type of hypersensitivity reaction?
Type IV (delayed)
What are the primary cells responsible for contact sensitization?
CD1a+/ CD141+ dermal dendritic cells
What are the cluster of immune cells in the elicitation phase
inducible skin associated lymphoid tissue
Define the types of allergic contact dermatitis:
- acute
- subacute
- chronic
- acute: erythema, edema, vesicles
- subacute: oozing, scaly juicy papules with weeping and crusting
- chronic: scaling, fissuring, lichenified erythematous plaques
hair allergens
- permanent hair dyes (but spares the scalp)
- permed/waved hair
- bleach
- relax
- permanent hair dyes (but spares the scalp): PPD
- permed/waved hair: GMT
- bleach: ammonium persulfate
- relax: sodium hydroxide
this allergen has a risk of active sensitization during patch testing
PPD