What is the first line of treatment for a patient with a history of eczema (atopic dermatitis) localized to the flexural areas of the inner elbow and buttocks?

First-Line Treatment for Flexural Eczema

For eczema localized to flexural areas (inner elbow and buttocks), initiate treatment with liberal emollient application combined with mild-potency topical corticosteroids (1% hydrocortisone) applied to affected areas during flare-ups. 1, 2

Treatment Algorithm

Step 1: Emollient Therapy (Foundation)

• Apply emollients liberally and frequently to maintain skin hydration and improve barrier function 1, 2
• Apply immediately after bathing to maximize effectiveness and prevent dryness 1, 2
• Replace regular soaps with soap substitutes (dispersable creams) to prevent removal of natural skin lipids 1, 2

Step 2: Topical Corticosteroid for Flares

• Use mild-potency topical corticosteroids (1% hydrocortisone) for flexural areas during active flares 1, 2
• Flexural areas (inner elbow, buttocks) have thinner skin and higher absorption rates, making them more susceptible to corticosteroid side effects 3
• Apply 2-3 times daily as a thin film until the flare resolves 4
• Use the least potent preparation required to control the eczema 1, 2

Step 3: Consider Moderate-Potency if Inadequate Response

• If mild corticosteroids fail after a reasonable trial (typically 1-2 weeks), escalate to moderate-potency topical corticosteroids 5, 6
• Moderate-potency corticosteroids result in treatment success in 52% versus 34% with mild-potency (OR 2.07,95% CI 1.41 to 3.04) 5
• Potent corticosteroids achieve even higher success rates (70% versus 39% with mild; OR 3.71,95% CI 2.04 to 6.72) but should be reserved for more severe cases given the flexural location 5

Application Frequency

• Once-daily application is as effective as twice-daily application for potent topical corticosteroids, though flexural eczema typically starts with mild potency 5, 6
• Apply for limited periods until flare resolves, not continuously 1, 2

Proactive Maintenance (After Initial Control)

• Consider twice-weekly application of topical corticosteroids to previously affected flexural areas to prevent relapse 2
• This proactive approach reduces relapse likelihood from 58% to 25% (RR 0.43,95% CI 0.32 to 0.57) 5

Adjunctive Management

• Sedating antihistamines may provide short-term relief during severe flares with significant itching, primarily through sedative effects 1, 2
• Non-sedating antihistamines have little to no value in atopic eczema 1, 2

Monitoring for Complications

• Watch for signs of secondary bacterial infection: crusting, weeping, or punched-out erosions 1, 2
• Treat bacterial infections (typically Staphylococcus aureus) with flucloxacillin 1
• Monitor for viral infections, particularly herpes simplex (eczema herpeticum), which requires prompt acyclovir treatment 1

Important Caveats for Flexural Areas

• Flexural sites (inner elbow, buttocks) are high-risk areas for corticosteroid side effects due to increased absorption and natural occlusion 3
• Short-term use (median 3 weeks) of mild to potent topical corticosteroids shows no evidence of increased skin thinning (low confidence evidence) 6
• Application-site reactions are least likely with topical corticosteroids compared to other anti-inflammatory agents 6
• Avoid very potent corticosteroids in flexural areas unless under specialist guidance 3

When to Refer to Dermatology

• Failure to respond to first-line treatment 1, 2
• Diagnostic uncertainty 1, 2
• When second-line treatments (topical calcineurin inhibitors, systemic therapy) are being considered 1, 2