Pathophysiology & Clinical Features

Atopic dermatitis (AD) is driven by epidermal barrier dysfunction (FLG filaggrin mutations, ceramide deficiency) and type 2 immune polarization (IL-4, IL-13, IL-31, and TSLP).

• Infantile Phase (<2 years): Acute weeping, crusted erythematous papulovesicles on cheeks, forehead, scalp, and extensor limbs (sparing the diaper area).
• Childhood & Adult Phase: Lichenified flexural plaques in antecubital and popliteal fossae, wrists, ankles, and eyelids.
• Complications: Staphylococcus aureus impetiginization and Eczema Herpeticum (punched-out monomorphic umbilicated vesicles requiring urgent oral/IV Acyclovir).

EASI Scoring & Targeted Systemic Escalation

• EASI (Eczema Area and Severity Index): Evaluates Erythema, Edema/Papulation, Excoriation, and Lichenification (0–3 each) across 4 body regions. EASI ≥ 21.1 indicates severe disease.
• Biologics (Dupilumab, Tralokinumab, Lebrikizumab): Safe in high-TB settings; no routine blood monitoring required.
• Oral Selective JAK1 Inhibitors (Upadacitinib 15–30 mg OD, Abrocitinib 100–200 mg OD): Rapid itch relief within 24–48 hours; requires baseline IGRA/TB, HBV/HCV panel, CBC, LFT, and lipids.