What is the treatment for an eczema flare with a secondary infection?

Treatment of Eczema Flare with Secondary Infection

For eczema flares with secondary bacterial infection, treat with topical corticosteroids as the primary therapy combined with oral flucloxacillin (or erythromycin if penicillin-allergic), while avoiding topical antibiotics which provide no additional benefit and may promote resistance. 1, 2

Identifying Secondary Infection

Before initiating treatment, confirm the presence of bacterial infection by looking for specific clinical features 1:

• Crusting or weeping of eczematous lesions suggests bacterial infection 1
• Grouped, punched-out erosions or vesiculation indicate herpes simplex infection (eczema herpeticum), not bacterial infection 1
• Bacteriological swabs are not routinely needed but may be necessary if patients fail to respond to treatment 1

First-Line Treatment: Topical Corticosteroids + Systemic Antibiotics

Topical Corticosteroids (Mainstay of Treatment)

Topical corticosteroids remain the cornerstone of treatment even when infection is present 1, 3:

• Use the least potent preparation required to control the eczema 1, 3
• Apply no more than twice daily 1, 3
• Very potent and potent preparations should be used with caution for limited periods only 1
• Stop corticosteroids for short periods when possible to minimize side effects 3

Systemic Antibiotics (For Overt Bacterial Infection)

Oral antibiotics are important for treating overt secondary bacterial infection 1, 3:

• Flucloxacillin is the first choice for Staphylococcus aureus, the most common pathogen 1, 3
• Phenoxymethylpenicillin should be given if β-hemolytic streptococci are isolated 1
• Erythromycin may be used when there is resistance to flucloxacillin or in patients with penicillin allergy 1, 3
• Treatment duration is typically 1 week 2

Critical Evidence on Topical Antibiotics

Avoid topical antibiotics (such as fusidic acid) as they provide no benefit and may be harmful 2:

• A high-quality randomized controlled trial (the CREAM study) demonstrated that topical fusidic acid resulted in worse subjective severity scores (POEM increased by 1.49 points) compared to placebo at 2 weeks 2
• Topical antibiotics also showed worse objective severity (EASI scores increased by 0.42) at 2 weeks 2
• The combination of topical steroid with topical antibiotic may provide only slight improvement over topical steroid alone (RR 1.10 for good/excellent improvement), but this evidence is of low quality 4

Special Consideration: Viral Infection (Eczema Herpeticum)

If herpes simplex infection is suspected based on grouped, punched-out erosions or vesiculation 1:

• Oral acyclovir should be given early in the disease course 1, 3
• In ill, feverish patients, acyclovir should be administered intravenously 1

Adjunctive Measures

Emollients and Bathing

• Continue regular bathing for cleansing and hydrating the skin 1, 3
• Apply emollients after bathing to provide a surface lipid film that retards water loss 1, 3
• Use dispersible cream as a soap substitute instead of soaps and detergents 1, 3

Antihistamines

• Sedating antihistamines may be useful as short-term adjuvants during severe pruritic episodes 1, 3
• Use primarily at night while asleep; avoid daytime use 1, 3
• Non-sedating antihistamines have little to no value in atopic eczema 1, 3

Common Pitfalls to Avoid

Do not routinely prescribe topical antibiotics for infected eczema in the community, particularly when signs of severe infection are absent 2. The CREAM study specifically showed that children with clinically infected eczema (69.6% with S. aureus cultured) did not benefit from antibiotics and potentially had worse outcomes 2.

Do not delay or withhold topical corticosteroids when infection is present—they remain the primary treatment 1, 3. The concern about using steroids during infection is unfounded when appropriate systemic antibiotics are given concurrently 1.

Recognize that most eczema flares with suspected infection are actually inflammatory flares, not true bacterial infections requiring antibiotics 2. Only treat with antibiotics when there are clear signs of bacterial infection (crusting, weeping) 1.