A 28-year-old woman presents to the emergency department with severe left eye pain, photophobia, and blurred vision for 3 days. On examination, she has a dendritic ulcer on the cornea with fluorescein staining. She has a history of recurrent oral cold sores. What is the most appropriate immediate management?

Explanation

## Diagnosis: Herpes Simplex Virus (HSV) Keratitis **Key Point:** Dendritic ulcer on corneal fluorescein staining is pathognomonic for HSV-1 keratitis. The patient's history of recurrent oral herpes (cold sores) confirms HSV reactivation. ## Management of HSV Keratitis **High-Yield:** HSV keratitis requires BOTH topical and systemic antiviral therapy to prevent scarring and vision loss. | Modality | Agent | Dosing | Duration | | --- | --- | --- | --- | | **Topical** | Acyclovir 5% ointment | 5 times daily | 10 days | | **Systemic** | Acyclovir | 400 mg 5 times daily | 10 days | | **Adjunct** | Cycloplegic drops (tropicamide) | For pain relief | As needed | **Clinical Pearl:** Topical corticosteroids are CONTRAINDICATED in epithelial HSV keratitis as they promote viral replication and cause geographic/amoeboid ulcers. They are only used in stromal disease under ophthalmologist supervision. **Mnemonic: AVOID steroids in HSV epithelial keratitis** — **A**ntiviral first, **V**iral replication worsens with steroids, **O**phthalmic referral needed, **I**ntense topical + systemic therapy, **D**endritic ulcer is the clue. ## Why This Approach? 1. **Epithelial healing:** Topical acyclovir penetrates corneal epithelium 2. **Systemic control:** Oral acyclovir prevents hematogenous spread and reduces recurrence risk 3. **Prevention of complications:** Reduces risk of stromal keratitis, scarring, and vision loss [cite:Harrison 21e Ch 172]