Can zoster ophthalmicus occur without a rash?

Herpes Zoster Ophthalmicus Can Occur Without Rash

Yes, herpes zoster ophthalmicus (HZO) can occur without a cutaneous rash, though this presentation is uncommon and can make diagnosis challenging. While the typical presentation includes a vesicular dermatomal rash, cases of "zoster sine herpete" (zoster without rash) can manifest with ocular complications despite the absence of skin lesions.

Clinical Presentation of HZO Without Rash

When HZO occurs without the characteristic vesicular rash, diagnosis may be based on:

• Orbital pain preceding other manifestations
• Ocular inflammation (conjunctivitis, keratitis, uveitis)
• Ophthalmoplegia
• Decreased visual acuity
• Ptosis
• Orbital inflammation visible on imaging

Diagnostic Considerations

The absence of rash creates diagnostic challenges:

• MRI findings may show enhancement of:

  • Extraocular muscles
  • Optic nerve sheath
  • Superior ophthalmic vein
  • Lacrimal gland 1

• Clinical suspicion should be high when patients present with:

  • Unilateral ocular pain
  • Ocular inflammation
  • History of varicella infection
  • Immunocompromised status
  • Advanced age

Ocular Complications

HZO can cause multiple ocular complications regardless of rash presence:

• Conjunctivitis
• Keratitis (epithelial, stromal)
• Uveitis/iritis
• Scleritis
• Optic neuritis
• Ocular hypertension/glaucoma
• Paralytic mydriasis
• Ptosis 2, 3

Management Approach

Early treatment is critical even when rash is absent:

1. Systemic antiviral therapy should be initiated as soon as HZO is suspected:

   • Acyclovir 800 mg five times daily for 7 days
   • Valacyclovir 1000 mg every 8 hours for 7 days
   • Famciclovir 500 mg three times daily for 7 days 4

2. Ophthalmology consultation is essential for:

   • Confirming diagnosis
   • Assessing extent of ocular involvement
   • Guiding specific ocular treatments

3. Topical treatments based on specific manifestations:

   • Topical antibiotics for prophylaxis against bacterial superinfection
   • Topical steroids (only after epithelial healing and under ophthalmologic supervision)
   • Mydriatics for iritis 4

4. Systemic steroids may be considered for severe inflammation, particularly:

   • Optic neuritis
   • Orbital inflammation
   • Severe anterior segment inflammation 2, 1

Special Considerations

• Immunocompromised patients require more aggressive treatment and closer monitoring 4
• Late complications can occur weeks to months after initial presentation 2
• Autoimmune mechanisms may be involved in delayed complications, potentially requiring immunomodulatory therapy 2

Pitfalls to Avoid

1. Delayed diagnosis due to absence of rash - maintain high index of suspicion with unilateral ocular pain and inflammation
2. Inappropriate steroid use - topical steroids should not be used without ophthalmologic consultation and never without antiviral coverage 4
3. Inadequate follow-up - patients require monitoring for delayed complications even after initial resolution
4. Missing systemic involvement - HZO can be associated with cranial nerve palsies and other neurological manifestations

Early recognition and prompt treatment of HZO, even without rash, is crucial to prevent vision-threatening complications and long-term sequelae such as post-herpetic neuralgia and vision loss.