Title: GZ / The Grenz Zone Season 1 / Episode 15
Tags: GZ DermnetNZ

Q: Separate from the atopic triad, atopic dermatitis is largely a clinical Diagnosis consisting of three essential features: 1) [subjective], 2) [objective],and 3) [...]
A: pruritus; eczematous rash; a chronic relapsing course

Q: Gene mutations in the [...] gene may contribute to atopic dermatitis
These patients may also be deficient in one to several types of [...], which are sphingolipids whose function is to hold corneocytes together in stratum corneum
A: filaggrin; ceramides
Back Extra: Filaggrin = Filament aggregating protein, which gets broken down into natural moisturization factor
"mortar” that holds corneocytes (“bricks”) together in stratum corneum)
Results: bad skin barrier, losing water and allowing outside things in

Q: Acute atopic dermative has an overactive Th_[...] response w/ ↑ IL4, 5, 13 vs chronic atopic derm has Th_[...] response
A: 2; 1
Back Extra: Acute = ↑ IL4, 5, and 13 to recruit more Th_2 cells, activate eosinophils, and increase IgE production
Chronic = ↑ IFN-γ and IL-12
Pregnancy induces a heavily Th_2 state, which explains the presence of acute atopic dermatitis in pregnancy

What are the 4 main pregnancy dermatoses
Atopic eruption of pregnancy, polymorphic eruption of pregnancy, pemphigoid (herpes) gestationis, and intrahepatic cholestasis of pregnancy
Back Extra: Polymorphic eruption of pregnancy = PUPP (pruritic urticarial papules and plaques of pregnancy)
Pregnancy is more of a Th_2 state, predisposing women to atopic flares

Q: Infantile atopic dermatitis (2 months – 2 yrs) presents with erythema and scale on the [...], scalp, and neck along w/ [...] arms and legs, and is very itchy and inflamed
A: cheeks; extensor
Back Extra: Can develop exudative plaques w/ Staph aureus colonization
Up to 90% of atopic derm pts are colonized with Staph aureus b/c their skin has ↓ antimicrobial peptides (vs psoriatic plaques having ↑ antimicrobial peptides = less likely to get infected)

Q: Why are patients with atopic dermatitis patients more likely to develop more exudative plaques with Staph aureus colonization compared to psoriasis patients?
[...]
A: Pts with AD have skin that has ↓ antimicrobial peptides (vs psoriatic plaques having ↑ antimicrobial peptides = less likely to get infected)
Back Extra: Up to 90% of atopic derm pts are colonized with Staph aureus due to decreased peptides such as human beta defensins and cathelicidins

Q: Childhood atopic dermatitis (2 months – 2 yrs) presents as “the itch that rashes”, with patients classically scratching their itchy [...] and [...] fossas, leading to classic excoriated lesions and lichenified plaques
A: antecubital; popliteal
Back Extra: Flexures

Q: Besides the excoriated lesions and lichenified plaques on flexural surfaces,there are several other signs that may aide in the diagnosis of atopic dermatitis, including [...] & [...] on the eyes and a(n) [...] on the nose
A: Dennie-Morgan lines; allergic shiners; exaggerated nasal crease (allergic salute)
Back Extra: Face & Neck: Pityriasis alba & hyperlinear neck folds; Extremities: hyperlinear palms, keratosis pilaris

Q: Besides the excoriated lesions and lichenified plaques on flexural surfaces,there are several other signs that may aide in the diagnosis of atopic dermatitis, including [...] on the face & [...] on the neck
A: Pityriasis alba; hyperlinear neck folds
Back Extra: Eyes: Dennie-Morgan lines and allergic shiners
Extremities: hyperlinear palms, keratosis pilaris

Q: Besides the excoriated lesions and lichenified plaques on flexural surfaces,there are several other signs that may aide in the diagnosis of atopic dermatitis, including [...] palms and & [...] on the extremities
A: hyperlinear; keratosis pilaris
Back Extra: Keratosis pilaris: follicular plugs or chicken skin on the outer arms, thighs, and buttocks
Eyes: Dennie-Morgan lines and allergic shiners
Face and neck: Pityriasis alba and hyperlinear neck folds

Q: Adolescent/Adult atopic dermatitis (12-60 yrs) has a similar presentation to adolescents w/ ↑ [...] eczema
A: hand
Back Extra: If struggling to tell whether it's psoriasis or eczema, try treating with calcipotriene. If it improves, it's probably psoriasis

What are some of the major triggers for atopic dermatitis?
F: Fragrances, fabrics food allergies
A: Allergens
D: Dry environments, Detergents
S: stress, smoking, sweating, soaps, showering
Back Extra: Think FADS!
F: Fragrances (laundry detergents or perfume), fabrics (wool or polyester), food allergies (wheat, eggs, milk, peanuts, and soy) A: Allergens (pet dander, dust mites)
D: dry environments, detergents
S: stress, smoking, sweating, soaps, showering (too long or too hot)

Q: Methods to detect Allergen specific IgE tests (type I hypersensitivity) include [...], which detect antigen-specific IgE in blood to various foods, insect venoms, medicine (penicillin), environmental allergen (pollen or dust mites), & work allergens (latex)
Skin Tests ([...] or [...]): detect allergen-specific IgE that activates mast cells in skin by causing a wheal and flare reaction, or contact dermatitis, respectively
A: allergy immunoassays; skin prick; patch testing
Back Extra: Advantages to immunoassay: Convenient, unaffected by medicines, and don't carry a risk for allergic reactions
Disadvantages: Lower specificity and higher cost
Skin testing advantages: Fast, more affordable, and more specific
Disadvantages: Risk of allergic reactions and anaphylaxis

Histologic findings for atopic dermatitis
Acute: spongiosis, perivascular lymphocytes and histiocytes with occasional eosinophils
Subacute: ↓ spongiosis and ↑ acanthosis
Chronic: ↓↓} spongiosis, ↑↑ acanthosis (may mimick psoriasiform disease) dermal fibrosis, hyperkeratosis
Back Extra: Usually a clinical diagnosis, but these are what biopsy findings would show
Acute
Subacute
Chronic

Q: Treatments for atopic dermatitis
[...] the skin daily
For prescription strength medications, may try low-mid potency [...] or topical [...] inhibitors
A: Moisturizing; topical steroids (e.g. fluocinolone,triamcinolone); calcineurin
Back Extra: Calcineurin inhibitors = tacrolimus, pimecrolimus
Also may try non-sedating antihistamines (loratidine) in morning then sedating antihistamines (diphenhydramine, hydroxyzine) at night
Crisaborole (eucrisa) is another topical treatment that is a PDE-4 inhibitor used to treat atopic dermatitis
Then systemic therapy if needed, narrow-band UVB, then prednisone, cyclosporine, azathioprine, mycophenolate mofetil, methotrexate, dupilumab

Q: [...] is a topical treatment that is [mechanism of action] used to treat atopic dermatitis
A: Crisaborole (eucrisa); a PDE-4 inhibitor
Back Extra: Same mechanism as otezla (apremilast)

Q: Tacrolimus and pimecrolimus both carry a black box warning for [...]
A: lymphoma
Back Extra: However, numerous recent meta-analysis with over 10 years of data have not shown an association

Q: What is the mechanism of action of dupilumab (Dupixent)?
[...]
A: Monoclonal antibody to IL-4 receptor
Back Extra: Thus blocking IL-4 and IL-13 intracellular signaling
Other systemic therapies include narrow-band UVB (often tried first), then prednisone, cyclosporine, azathioprine, mycophenolate mofetil, and methotrexate

Q: What are common side effects of dupilumab (Dupixent)?
[...]
A: Dry eyes, conjunctivitis, keratitis
Back Extra: Most common side effects involve the eye

Q: In atopic dermatitis, [...]% of cases begin by age 1, and [...]% resolve by 12 years of age
A: 60; 60
Back Extra: 60% rule