Eczematous Eruption Flashcards
Describe Lichen Simplex Chronicus
Patch-like, leather-like, higher, hardened skin markings, circumscribed plaque, exaggerated skin lines
What is another name for Lichen Simplex Chronicus?
“Neurodermatosis”
What causes Lichen Simplex Chronicus?
Chronic scratching- this is a learned behavior and is the end stage of itchy (pruritic) and eczematous disorders including topic dermatitis
Where is Lichen Simplex Chronicus most common?
Nape of Neck, back of feet and ankles (also external forearms, lower legs, scrotum, and vulva)
What does circumscribed plaque mean?
confined to a limited area
DDx for Lichen Simplex Chronicus?
not provided in slides
psoriasis, lichen planus, nummular dermatitis (p 104)
What is the treatment for Lichen Simplex Chronicus?
- Break the cycle of itching (it is a learned behavior)
- High potency glucocorticoids w/ occlusion to penetrate more/ or intralesional injection of glucocorticoids
- Oral Antihistamine (hydroxyzine or tricyclic antidepressants with antihistamanic activity ex. doxepine)
- Higher doses of antihistamine- but people don’t want sedation–although can help them stop the scratching!
Where should a high potency of glucocorticoids be used on skin?
thicker skin areas / thicker lesions
What does recalcitrant mean?
stubborn
Name 1 oral antihistamine and 1 tricyclic antidepressant w/ antihistaminic activity that is used to treat Lichen Simplex Chronicus
- Hydroxyzine
2. Doxepine
Define Pruritic
Itchy!
Name 4 descriptors of skin lesions
- distribution of eruption
- types of primary and secondary lesions
- shape of individual lesions
- arrangement
What should you be checking for during a skin exam?
Skin, Hair, Nails, Mucous Membrane of Mouth, Eyes, Nose, Nasopharynx, Anogenital
What is the diagnostic criteria for atopic dermatitis?
pruritus, typical morphology and distribution (lichenification, and nipple/eyelid/hand eczema)
onset in childhood
personal or family history of asthma, allergic rhinitis, atopic derm
xerosis
When does atopic derm present?
before 5 years old in 90% of patients
occurs in 10-20% of children
The mutation of the filaggrin gene is associated with which type eczematous eruption?
atopic dermatitis
Describe acute, subacute, chronic atopic derm.
acute: very itchy lesions, erythematous papules, excoriation, vesicles w/ serous exudate
subacute: erythematous, excoriated, SCALING
chronic: LICHENIFICATION, fibrotic papules, hyper/hypo pigmentation
Where does atopic derm appear on adults? children?
adults–flexural folds
children–extensor surfaces, face/scalp, SPARES diaper
What are the foods associated with risk factors for atopic derm? (a cause in 1/3-1/2 of children)
foods: egg, soy, shellfish, meat, peanuts, wheat, fish (90% of food-induced cases)
many allergies self-resolve within first 5 years
allergens may be trigger for IgE autoreactivity to epithelial autoantigens in young children
What are general risk factors for atopic derm?
mutation of filaggrin gene, term IDMs, obesity, environmental allergens, contact irritants, aeroallergens (dust, mold, pollen, dander), microbial agents (S. aureus, pityrosporum yeasts, candida organisms, trichophyton dermatophytes), stress
What are the lab findings of atopic derm?
high serum IgE, eosinophilia, S aureus, RAST=specific IgE to milk, egg, peanut, fish correlates over 95% of time to symptoms
negative skin tests have high negative predictive value, ruling out a specific antigen
positive skin tests-lower correlation with food allergies
What are environmental treatments for atopic derm?
avoidance of irritants, allergens increase humidity do not bathe more than once daily--careful about soaps avoid specific foods dust might mitigation stress reduction
Medicines for atopic derm treatment?
Hydration: soak with prompt application of barrier ointment/cream
moisturizers/occlusives: avoid fragrances
**ointments>creams>lotions>solutions
Corticosteroids: low potency in face/groin–reduce inflammation,itch
Topical calcineurin inhibitors: tacrolimus (Elidel) & pimecrolimus (protopic)
Tar preparations: shampoos, may cause irritation, dryness, photosensitivity rxns, folliculitis
Wet dressings: use with topical corticosteroids to reduce scratching + hydrate in severe cases
antibiotics: topical ointments for erythema, crusting (mupirocin or OTC), oral antibiotics (against S aureus) for extensive legions, prophylactic treatment, approaches w/ MRSA (bleach baths/phisohex/nasal mupirocin)
antipruritic: avoid topical (sensitization), sedating antihistamines
Methoxypsoralen w/ UVA
immunosuppressive therapy (cyclosporine)
What do tacrolimus and pimecrolimus do?
inhibit transcription of proinflammatory cytokines
use sunscreen
associated wit T cell lymphoma
burning may occur but may resolve with continued treatment
do not atrophy skin & can be used on face & eyelids
What are the characteristics of sebhorrheic dermatitis?
- common, chronic
- greasy scales overlying erythematous patches or plaques
- coexists with psoriasis
- scalp (dandruff), eyebrows, eyelids, nasolabial folds, glabella, external auditory canal, postauricular areas, central chest, axilla, groin, submammary folds, gluteal cleft
- not always itchy
What age of life do you get sebhorreic derm?
first few weeks usually on face, scalp, groin, up until 6 months
recurs at puberty/adulthood
-seen in Parkinson’s, HIV infection, acutely ill patients, CVAs
-MAJORITY have NO UNDERLYING DISORDER!