Msk Dermatology · Year 2 · from Msk Dermatology
Case 2: Atopic Dermatitis with Eczema Herpeticum
Patient Presentation
Demographics: 8-year-old female
Chief Complaint: Sudden worsening of eczema with fever and painful blisters
History of Present Illness: The patient has had atopic dermatitis since infancy. Her eczema has been poorly controlled despite topical corticosteroids and moisturizers. Three days ago, she developed painful, grouped vesicles on her face and arms in areas of active eczema. She has a fever of 38.9C and appears ill. The lesions are spreading rapidly.
Past Medical History:
- Atopic dermatitis since age 6 months
- Allergic rhinitis
- Asthma
Family History:
- Mother has asthma and allergic rhinitis
- Brother has atopic dermatitis
Physical Examination:
- Temperature: 38.9C
- General: Ill-appearing
- Skin:
- Widespread eczematous patches on flexural surfaces
- Multiple punched-out vesicles and erosions on face and arms
- Some vesicles with hemorrhagic crusting
- Dennie-Morgan folds (infraorbital creases)
- Lichenification in antecubital and popliteal fossae
- Lymph nodes: Tender cervical lymphadenopathy
Workup and Results
Laboratory Studies:
- WBC: 14,200/mcL with left shift
- HSV PCR from vesicle fluid: Positive for HSV-1
Clinical Assessment:
- Eczema herpeticum (Kaposi varicelliform eruption) complicating atopic dermatitis
Clinical Image
Clinical photograph showing eczema herpeticum with characteristic "punched-out" erosions and vesicles superimposed on eczematous skin, a dermatologic emergency in patients with atopic dermatitis.
Diagnosis
Eczema Herpeticum (Kaposi Varicelliform Eruption)
Complicating severe atopic dermatitis with:
- "Atopic triad" present (eczema, asthma, allergic rhinitis)
- Filaggrin-related barrier dysfunction
- HSV-1 dissemination in compromised skin
Discussion
This case illustrates atopic dermatitis and its complications:
- Atopic Triad: The lecture describes the "atopic triad" of eczema, allergic rhinitis, and asthma. This patient demonstrates all three, along with a strong family history of atopy.
- Filaggrin Mutations: The lecture explains that filaggrin mutations lead to barrier dysfunction, a key factor in atopic dermatitis pathogenesis. This barrier defect allows easy entry of pathogens including HSV.
- Distribution by Age: The lecture notes that infants have face, scalp, and extensor involvement, while children and adults have flexural surface involvement (antecubital, popliteal). This patient shows the classic pediatric pattern.
- Eczema Herpeticum: The lecture identifies eczema herpeticum as a serious complication caused by herpes simplex virus. It is a dermatologic emergency requiring antiviral therapy.
Treatment Plan
- Antiviral Therapy (Urgent):
- IV acyclovir 10 mg/kg every 8 hours
- Continue until no new lesions for 48 hours
- Then transition to oral valacyclovir to complete 10-14 day course
- Supportive Care:
- IV fluids for hydration
- Pain management
- Ophthalmology consultation (rule out ocular involvement)
- Wound Care:
- Gentle cleansing
- Non-adherent dressings
- Monitor for secondary bacterial infection
- Long-term Atopic Dermatitis Management:
- After HSV resolution, resume emollient therapy
- Consider dupilumab (anti-IL-4/IL-13) for poorly controlled disease
- Bleach baths to reduce S. aureus colonization
Teaching Points
- Atopic triad: Eczema, allergic rhinitis, asthma
- Filaggrin mutations cause barrier dysfunction in atopic dermatitis
- IL-4 and IL-13 are key cytokines (Th2 response) - targeted by dupilumab
- Eczema herpeticum is an emergency requiring IV antiviral therapy
- Dennie-Morgan folds are infraorbital creases associated with atopy