What are the diagnostic and treatment considerations for herpes zoster (shingles) of the face and eye?

Diagnostic and Treatment Considerations for Herpes Zoster of the Face and Eye

Prompt treatment with oral antiviral therapy within 72 hours of symptom onset is essential for herpes zoster affecting the face and eye to reduce the risk of complications including postherpetic neuralgia and ocular damage. 1

Diagnosis

• Clinical presentation:

  • Unilateral dermatomal distribution of vesicular lesions on the face
  • Prodromal symptoms (burning, tingling, pain) 24-72 hours before rash appearance
  • Progressive development of lesions over 4-6 days
  • When affecting the ophthalmic division of the trigeminal nerve (V1), called herpes zoster ophthalmicus

• Ocular manifestations may include:

  • Conjunctivitis
  • Keratitis (dendritic or stromal)
  • Pseudodendrites
  • Corneal scarring or vascularization
  • Uveitis/iritis
  • Sectoral iris atrophy
  • Secondary glaucoma 2

Treatment Approach

1. Systemic Antiviral Therapy

First-line treatment (start within 72 hours of rash onset):

• Valacyclovir: 1000 mg three times daily for 7 days 3

  • Preferred due to better bioavailability and more convenient dosing regimen 4

• Famciclovir: 500 mg three times daily for 7 days 5

  • Also shows superior reduction in herpes zoster-associated pain compared to acyclovir 4

• Acyclovir: 800 mg five times daily for 7 days 1, 6

  • Less convenient dosing schedule but effective when started early

Special considerations:

• Immunocompromised patients may need more aggressive treatment, including IV acyclovir initially 1
• Treatment should continue until all lesions have crusted over 1
• Extending treatment beyond 7 days has not shown significant additional benefits 7

2. Ocular Management

• For conjunctivitis:

  • Topical antibiotics may be needed to prevent secondary bacterial infection of vesicles 2
  • Topical antivirals alone have not been shown to be helpful in treating VZV conjunctivitis but may be used as adjunctive treatment in unresponsive cases 2

• For keratitis/uveitis:

  • Ophthalmology consultation is recommended for any patient with eye involvement 8
  • Topical corticosteroids may be beneficial for inflammatory complications but should be used with caution and in conjunction with systemic antiviral therapy 2
  • Corticosteroids with poor ocular penetration (fluorometholone, loteprednol) may be less likely to cause elevated IOP or cataract formation 2

3. Pain Management

• Acute pain:

  • Mild pain: NSAIDs or acetaminophen
  • Moderate to severe pain: Gabapentin, pregabalin, or tricyclic antidepressants
  • Severe refractory pain: Short-term opioids as last resort 1

• Postherpetic neuralgia (pain persisting beyond acute phase):

  • First-line options: Gabapentin, pregabalin, tricyclic antidepressants (nortriptyline, desipramine), SNRIs (duloxetine, venlafaxine), and topical lidocaine 1
  • When using tricyclic antidepressants, start with lower doses and titrate slowly to minimize anticholinergic side effects 1

Follow-up Recommendations

• Follow-up within 1-2 weeks to assess:
  • Resolution of cutaneous lesions
  • Persistence of pain
  • Development of ocular complications 1
• Regular monitoring of patients on topical corticosteroids:
  • Measure visual acuity and IOP
  • Perform slit-lamp biomicroscopy 2
• Extended follow-up for patients at high risk of postherpetic neuralgia 1

Prevention of Complications

• Late ocular complications can occur in up to 29% of treated patients versus 50-71% of untreated patients 7
• Postherpetic neuralgia risk is significantly reduced with prompt antiviral therapy 7
• Chronic sequelae may include dry eye and corneal anesthesia with neurotrophic keratitis 2

Common Pitfalls to Avoid

1. Delayed treatment - Starting antivirals after 72 hours significantly reduces efficacy
2. Inadequate dosing - Using lower than recommended doses of antivirals
3. Missing ocular involvement - Failing to perform thorough eye examination in facial zoster
4. Using topical corticosteroids without antiviral coverage - This can potentiate viral infection
5. Inadequate pain management - Underestimating the severity of acute and chronic pain

Early recognition and aggressive management of herpes zoster ophthalmicus are critical to limit visual morbidity and prevent long-term complications such as postherpetic neuralgia.