Dermatitis, Atopic

Source: Law RM, Kwa PG. Atopic Dermatitis. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 8th ed. http://accesspharmacy.com/content.aspx?aid=7999376. Accessed May 27, 2012.

• Eczema

• Chronic, inflammatory skin eruption associated with red patches and intense itching; usually begins in infancy and may continue into adult life.

• Genetic, environmental, and immunologic mechanisms

• Affects 15–30% of children and 2–10% of adults in developed countries.
• Prevalence has increased over past 3 decades.

• Family history of atopic diseases (e.g., hay fever, asthma)

• Neuropeptides, irritation, or scratching causes release of proinflammatory cytokines from keratinocytes.
• Alternatively, allergens in epidermal barrier or in food may cause T-cell mediated reactions.

Signs and Symptoms

• Presentation depends on age.
• In infancy, erythematous, patchy, pruritic, papular skin rash may first appear on cheeks and chin and progress to red, scaling, oozing lesions. Affects malar region of the cheeks, forehead, scalp, chin, and behind ears while sparing nose and paranasal creases. Lesions spread over several weeks to extensor surfaces of the lower legs (due to crawling); may involve entire body except diaper area and nose.
• In childhood, skin often appears dry, flaky, rough, and cracked; scratching may cause bleeding and lichenification.
• In adults, lesions are more diffuse with underlying erythema. The face is commonly involved; may be dry and scaly. Lichenification may be seen.

Means of Confirmation and Diagnosis

• Based primarily on patient history, signs, and symptoms.
  • Family or personal history of asthma, hay fever, or other atopic diseases
  • Dry and flaky skin with pruritus
  • Early age of onset
  • Chronic and relapsing courses

Laboratory Tests

• Allergy skin testing may help identify factors that trigger flares.

Differential Diagnosis

• Contact dermatitis
• Scabies
• Seborrheic dermatitis
• Psoriasis
• Tinea infection

• Relieve symptoms.
• Prevent recurrences.
• Avoid adverse treatment effects.
• Improve quality of life.

• Give lukewarm baths to infants and children.
• Apply lubricants/moisturizers immediately after bathing.
• Use scent-free moisturizers liberally each day.
• Keep fingernails short.
• Select clothing made of soft cotton fabrics.
• Consider sedating oral antihistamines to reduce scratching at night.
• Avoid situations that cause overheating.
• Learn to recognize skin infections and seek treatment promptly.
• Identify and remove irritants and allergens.
• Phototherapy may be attempted for dermatitis not controlled by calcineurin inhibitors. It may also permit use of lower-potency corticosteroids or eliminate need for corticosteroids.

• Topical Corticosteroids
  • Use low-potency agents (e.g., hydrocortisone 1%) on face, and medium-potency products (e.g., betamethasone valerate 0.1%) for body.
  • Avoid potent fluorinated corticosteroids on face, genitalia, and intertriginous areas, and in infants.
  • Use mid-strength and high-potency corticosteroids for short-term management of exacerbations.
  • Reserve ultra-high and high-potency agents (e.g., betamethasone dipropionate 0.05%, clobetasone propionate 0.05%) for short-term treatment of lichenified lesions in adults.
  • May use a lower-potency agent for maintenance if needed after lesions have improved substantially.
• Topical Immunomodulators
  • Recommended as second-line treatments due to concerns about possible cancer risk. Use sunscreen with sun protection ...