Atopic dermatitis — Viva

Q1: Definition and epidemiology (2 min)

What is atopic dermatitis? Give Nutten 2015 prevalence figures and the comorbidities Langan lists. ^[23][1]

Model: Chronic inflammatory skin disease; eczematous lesions and intense itch. Up to 20% of children and up to 3% of adults; still increasing, especially in low-income countries. First manifestations usually early in life and often precede asthma or allergic rhinitis. Associated with food allergy, asthma, allergic rhinitis and mental-health disorders; leading cause of the global burden from skin disease.^[23][1]

Q2: Distribution and differential (3 min)

How does distribution change with age? Give the one-line discriminator from psoriasis. ^[1]

Model: Infants — face, scalp, extensors, trunk. Children — flexures (antecubital and popliteal fossae). Adolescents/adults — flexures, hands, head-and-neck. Poorly demarcated and itchy in flexures is AD; well-demarcated silvery scale on extensors is psoriasis. ^[1]

Q3: Severity scoring (2 min)

Recite the Leshem EASI bands and the Measure Up / JADE MONO-1 entry set. ^[22][9]

Model: 0 clear; 0.1–1.0 almost clear; 1.1–7.0 mild; 7.1–21.0 moderate; 21.1–50.0 severe; 50.1–72.0 very severe. Entry: EASI ≥16, IGA/vIGA-AD ≥3, BSA ≥10%. Do not add an unsourced DLQI ≥11 as a fourth AAD number.^[22][9]

Q4: Systemic ladder (3 min)

AAD 2024 strong vs conditional vs against. Quote SOLO IGA 0/1 and Measure Up 1 EASI-75. ^[12][8][9]

Model: Strong: dupilumab, tralokinumab, abrocitinib, baricitinib, upadacitinib. Conditional: phototherapy, azathioprine, ciclosporin, methotrexate, mycophenolate. Against systemic corticosteroids. SOLO 1: IGA 0/1 38% q2w and 37% weekly vs 10% placebo (671 adults). Measure Up 1: EASI-75 70% (15 mg) and 80% (30 mg) vs 16% placebo (847 randomised).^[12][8][9]

Q5: Emergency and harm (2 min)

Eczema herpeticum. Two preventable harms from the wrong steroid or the wrong systemic. ^[1][12]

Model: Monomorphic punched-out erosions plus fever → systemic aciclovir, consider admission. Do not use potent steroids long-term on the face/eyelids. Do not use oral corticosteroids for chronic AD (AAD against; rebound). Monitor ciclosporin BP/creatinine and azathioprine FBC/LFTs.^[1][12]

References6ShowHide

1. [1]Langan SM, Irvine AD, Weidinger S. Atopic dermatitis. Lancet, 2020.PMID 32738956
2. [8]Simpson EL, Bieber T, Guttman-Yassky E, et al. Two Phase 3 Trials of Dupilumab versus Placebo in Atopic Dermatitis. N Engl J Med, 2016.PMID 27690741
3. [9]Guttman-Yassky E, Teixeira HD, Simpson EL, et al. Once-daily upadacitinib versus placebo in adolescents and adults with moderate-to-severe atopic dermatitis (Measure Up 1 and Measure Up 2). Lancet, 2021.PMID 34023008
4. [12]Davis DMR, Drucker AM, Alikhan A, et al. Guidelines of care for the management of atopic dermatitis in adults with phototherapy and systemic therapies. J Am Acad Dermatol, 2024.PMID 37943240
5. [22]Leshem YA, Hajar T, Hanifin JM, Simpson EL What the Eczema Area and Severity Index score tells us about the severity of atopic dermatitis: an interpretability study. Br J Dermatol, 2015.PMID 25580670
6. [23]Nutten S Atopic dermatitis: global epidemiology and risk factors. Ann Nutr Metab, 2015.PMID 25925336