Atopic Flashcards
*Atopic Dermatitis
is a chronic autoimmune, pruritic (itchy), and inflammatory skin condition most commonly affecting children worldwide (5–20%).
- It often presents in early childhood and tends to affect skin creases and flexure surfaces.
Atopic dermatitis is often associated with allergic rhinitis and asthma, forming the atopic triad.
Approximately 80% of individuals with atopic dermatitis develop one or both of the other conditions.
- Food allergies (e.g., to eggs, milk, peanuts) are more common in these patients.
Defective Epidermal Barrier**: Includes a deficiency in filaggrin, imbalances in protease activity, and tight junction abnormalities.
Immune Dysregulation**: Involves reduced function of TLR2 and TLR9 (innate immune system) and increased expression of TH2, TH17, and TH22 cytokines (adaptive immune system)
Risk Factors**: Family history (genetics), allergies, and environmental factors like hard water.
Protective Factors**: Early exposure to daycare, pets, and farm animals, supporting the hygiene hypothesis.
Can’t rely solely on a visual examination due to variability in appearance.
topic Stigmata**: Skin findings include keratosis pilaris, Denny-Morgan folds, Hertoghe’s sign, Pityriasis alba, palmar hyperlinearity, and retroauricular fissuring.
Generally clinical, based on itchy, erythematous lesions typically found in skin folds.
- UK Criteria: Requires pruritic lesions plus at least three additional criteria (e.g., involvement of skin creases, history of asthma/hay fever, chronic dryness, early onset).
Management and Treatment:
Avoid Triggers**: Environmental factors, stress, and possibly specific foods. The role of diet is controversial (e.g., dairy inclusion/exclusion).
- Medications:
- Topical corticosteroids: For local application except on face/eyelid/skin folds due to skin thinning risk.
- Topical calcineurin inhibitors: An alternative for sensitive areas.
- Phototherapy: For severe cases.
