In a patient being treated with antiviral medication for herpes zoster who now has an open, oozing lesion, what additional management is indicated?

Management of Open, Oozing Herpes Zoster Lesions During Antiviral Treatment

When herpes zoster lesions open and begin to ooze during antiviral therapy, you must implement strict infection control measures, assess for secondary bacterial infection, continue antiviral therapy until complete crusting occurs, and consider treatment escalation if the patient is immunocompromised or shows signs of dissemination. 1

Immediate Assessment and Infection Control

Implement contact precautions immediately to prevent transmission to susceptible individuals, as open vesicular lesions are highly contagious to anyone who has not had chickenpox or vaccination. 1 The patient should:

• Cover all lesions with clothing or occlusive dressings to minimize viral shedding 1
• Avoid contact with pregnant women, immunocompromised individuals, and anyone without varicella immunity until all lesions have completely crusted 1, 2
• Maintain physical separation of at least 6 feet from others in healthcare settings 1

For disseminated zoster (≥3 dermatomes) or immunocompromised patients, implement both airborne and contact precautions in addition to standard precautions. 1

Evaluate for Secondary Bacterial Infection

Assess the oozing lesions for signs of bacterial superinfection, which is a common complication when vesicles rupture:

• Look for increased erythema, warmth, purulent drainage, or expanding cellulitis beyond the dermatomal distribution 3
• If secondary bacterial infection is present, add topical mupirocin ointment three times daily to affected areas, which may be covered with gauze dressing 4
• For more extensive bacterial infection, consider systemic antibiotics targeting Staphylococcus aureus and Streptococcus species 3

Continue and Potentially Extend Antiviral Therapy

Do not discontinue antiviral therapy at an arbitrary 7-day mark if lesions are still forming or have not completely scabbed. 1, 2 The key clinical endpoint is complete crusting of all lesions, not calendar days. 1

• Continue oral valacyclovir 1 gram three times daily or acyclovir 800 mg five times daily until all lesions have scabbed 1, 2
• Treatment may need to extend beyond 7-10 days, particularly in immunocompromised patients who develop new lesions for 7-14 days and heal more slowly 1
• Monitor for complete healing of lesions as the primary treatment endpoint 1

Consider Treatment Escalation

Switch to intravenous acyclovir 10 mg/kg every 8 hours if any of the following are present: 1, 2

• Disseminated disease (≥3 dermatomes, visceral involvement, or hemorrhagic lesions) 1
• Severe immunosuppression (active chemotherapy, HIV with low CD4 count, organ transplant) 1, 2
• Lesions fail to begin resolving within 7-10 days of oral therapy 1
• CNS complications (encephalitis, meningitis) or complicated ocular/facial disease 1, 2

For immunocompromised patients with disseminated or invasive herpes zoster, temporarily reduce or discontinue immunosuppressive medications when clinically feasible, and do not restart until all vesicular lesions have crusted and fever has resolved. 1, 2

Wound Care and Symptomatic Management

Provide appropriate local wound care to promote healing and prevent complications:

• Keep the skin well hydrated with emollients after lesions have crusted, but avoid applying any products to active vesicular lesions 1
• Apply topical ice or cold packs to reduce pain and swelling during the acute phase 1
• Maintain good hygiene to prevent secondary bacterial infection 3

Monitor for Treatment Failure or Resistance

If lesions have not begun to resolve within 7-10 days despite appropriate antiviral therapy, suspect acyclovir resistance: 1

• Obtain viral culture with susceptibility testing 1
• Acyclovir resistance occurs in up to 7% of immunocompromised patients but is extremely rare in immunocompetent individuals 1
• For confirmed acyclovir-resistant VZV, switch to foscarnet 40 mg/kg IV every 8 hours until clinical resolution 1, 2

Common Pitfalls to Avoid

• Do not stop antiviral therapy at exactly 7 days if lesions are still active – this is inadequate for VZV infection and may lead to prolonged viral replication 1
• Do not apply topical antivirals – they are substantially less effective than systemic therapy and are not recommended 1, 2
• Do not use topical corticosteroids on active lesions – this can worsen viral replication and increase risk of dissemination, particularly in immunocompromised patients 1
• Do not assume oozing is normal progression – always assess for secondary bacterial infection requiring additional treatment 3