A 28-year-old man with newly diagnosed HIV (CD4 count 85 cells/μL) presents with severe pain and vesicular eruption in the ophthalmic division (V1) of the trigeminal nerve on the right side. Vesicles are present on the tip of the nose and right eyelid. He denies prior chickenpox but was vaccinated against varicella as a child. Ophthalmology confirms corneal involvement. What is the most appropriate immediate management?

Explanation

## Herpes Zoster Ophthalmicus in Advanced HIV: Urgent Management ### Clinical Context: Hutchinson's Sign **Key Point:** Vesicles on the tip of the nose (Hutchinson's sign) indicate involvement of the nasociliary branch of V1 and predict a 50% risk of ocular complications, including corneal scarring, uveitis, and vision loss. This is a dermatologic emergency. ### Why IV Acyclovir Is Mandatory | Criterion | Rationale | |-----------|----------| | **CD4 <100** | Severe immunosuppression increases risk of disseminated VZV, post-herpetic neuralgia, and ocular complications | | **Corneal involvement** | Requires high CNS/aqueous humor penetration; IV acyclovir achieves superior levels vs. oral formulations | | **V1 distribution** | Ophthalmic zoster carries 50–70% risk of ocular sequelae if not aggressively treated | | **Systemic risk** | CD4 <100 confers risk of VZV vasculopathy (stroke) and disseminated disease | ### Treatment Algorithm ```mermaid flowchart TD A["Herpes zoster ophthalmicus + CD4 <100"]:::outcome --> B{"Corneal involvement?"}:::decision B -->|Yes| C["IV acyclovir 10-15 mg/kg 8-hourly"]:::action B -->|No| D["Consider IV acyclovir vs. high-dose oral"]:::action C --> E["Urgent ophthalmology referral"]:::action D --> E E --> F["Initiate/optimize ART"]:::action F --> G["Monitor for immune recovery uveitis"]:::outcome C --> H["Analgesia: pregabalin, NSAIDs"]:::action ``` ### Dosing & Duration **High-Yield:** IV acyclovir for disseminated or ophthalmic zoster in immunocompromised hosts: - **Dose:** 10–15 mg/kg IV every 8 hours - **Duration:** 10–14 days (longer than immunocompetent hosts) - **Renal monitoring:** Adjust for creatinine clearance; risk of crystalline nephropathy ### Adjunctive Management 1. **Ophthalmology co-management:** Essential for corneal assessment, anterior chamber inflammation, and potential need for topical corticosteroids (controversial; may increase risk of dissemination but may reduce inflammation) 2. **Antiretroviral therapy:** Initiate or optimize; CD4 recovery is the ultimate goal 3. **Analgesia:** Pregabalin 150–600 mg/day or gabapentin for neuropathic pain 4. **Monitoring:** Watch for immune recovery uveitis (IRU) as CD4 rises >100 cells/μL ### Why Oral Antivirals Are Insufficient **Warning:** Oral valacyclovir achieves only ~50% of IV acyclovir CSF/aqueous humor levels. In CD4 <100 with corneal involvement, oral therapy risks: - Inadequate viral suppression - Progressive corneal scarring - Disseminated VZV (meningitis, vasculopathy) ### Mnemonic: CORNEAL Zoster in Advanced HIV - **C**D4 <100 → IV therapy mandatory - **O**phthalmic division (V1) → high complication risk - **R**etinal/corneal involvement → urgent ophthalmology - **N**eeds IV acyclovir 10–15 mg/kg 8-hourly - **E**mergency: dissemination risk (meningitis, stroke) - **A**RT optimization essential for immune recovery - **L**ong-term: monitor for immune recovery uveitis **Clinical Pearl:** Hutchinson's sign (vesicles on nose tip) is a clinical red flag for ocular involvement and should trigger immediate ophthalmology referral and IV antiviral therapy, regardless of CD4 count.