What is the management of eczema herpeticum?

Management of Eczema Herpeticum

Eczema herpeticum requires immediate treatment with systemic antiviral therapy, specifically acyclovir, which has significantly reduced mortality rates from this potentially fatal condition. 1

Diagnosis and Clinical Features

• Eczema herpeticum presents as disseminated herpes simplex virus infection on eczematous skin, characterized by grouped, punched-out erosions or vesiculation 2
• Deterioration in previously stable atopic dermatitis may indicate secondary viral infection 2
• The condition can be rapidly progressive and is considered a dermatologic urgency due to increased patient morbidity 1, 3

Primary Treatment Algorithm

Antiviral Therapy

• First-line treatment: Systemic acyclovir 1, 2
  • For ill, febrile patients: Intravenous acyclovir administration 2, 4
  • For non-febrile, less severe cases: Oral acyclovir 4
• Early initiation of acyclovir is critical and directly correlates with decreased length of hospital stay 1
• Before the advent of acyclovir, untreated eczema herpeticum had a 10-50% mortality rate 1

Management of Bacterial Superinfection

• Add systemic antibiotics only when there is clinical evidence of bacterial superinfection 2, 4
• First-line antibiotic for Staphylococcus aureus (most common bacterial pathogen): Flucloxacillin 2, 4
• For penicillin-allergic patients: Erythromycin 2
• For β-hemolytic streptococci: Phenoxymethylpenicillin 2

Symptomatic Management

• For pruritus: Sedating antihistamines (especially at night) 2, 4
  • Chlorphenamine (chlorpheniramine) 4-12 mg at night is an option 4
  • Note: Non-sedating antihistamines have little to no value in controlling itch 4
• For fever: Appropriate antipyretics 2
• Topical options for itch relief:
  • Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) 4
  • Ichthammol (1% in zinc ointment) for lichenified areas 4

Important Clinical Considerations

Monitoring and Follow-up

• Assess response to therapy within 48-72 hours 4
• Monitor for signs of clinical improvement including fever resolution and involution of rash 3
• After resolution of the acute infection, resume maintenance therapy for underlying atopic dermatitis 2

Cautions and Special Populations

• No specific recommendations unique to the pediatric population for antimicrobial treatment 1
• For patients with hepatic impairment: Avoid chlorphenamine and hydroxyzine in severe liver disease 4
• For patients with renal impairment: Halve the dose of hydroxyzine 4

Common Pitfalls

• Delayed diagnosis and treatment can lead to significant morbidity and potential mortality 3, 5
• Eczema herpeticum can be mistaken for other conditions such as Stevens-Johnson syndrome, impetigo, or disseminated herpes zoster 6
• Tachyphylaxis may develop with prolonged use of antihistamines 4
• Herpetic lesions only affect areas with active atopic dermatitis; skin without AD lesions is typically not affected 7

Risk Factors for Recurrent Eczema Herpeticum

• Early onset of atopic dermatitis 7
• Extrinsic atopic dermatitis (IgE-mediated) 7
• Severe atopic distortion 7

The management of eczema herpeticum has evolved significantly since the introduction of acyclovir, transforming it from a potentially fatal condition to a manageable dermatologic urgency when treated promptly and appropriately 1, 8.