Keratitis: Inflammatory Corneal Disorders
Ophthalmology: Infectious and Non-Infectious Corneal Ulceration
1. Categorization by Etiology
| Type | Classic Presentation/Risk |
|---|---|
| Bacterial | Contact lens use (Pseudomonas), purulent discharge, dense central ulcer. |
| Viral (Herpes Simplex) | Dendritic ulceration (stains with fluorescein), reduced corneal sensation. |
| Fungal | Vegetative trauma, indolent course, feathery borders, satellite lesions. |
| Acanthamoeba | Severe pain disproportionate to findings, ring infiltrate, often associated with water exposure/hot tubs. |
2. Clinical High-Yield Pearls
- Urgency: Bacterial and Acanthamoeba keratitis are sight-threatening emergencies requiring urgent scraping, cultures, and aggressive antimicrobial therapy.
- Contraindication: Topical steroids are generally contraindicated in infectious keratitis (especially fungal and herpes simplex) as they can promote rapid microbial progression and perforation.
- Diagnostic Tool: Always use fluorescein staining to delineate the size, shape, and depth of the corneal epithelial defect.
- Educational Resource: For comprehensive infectious disease management algorithms, clinical imaging, and practice questions, visit mymedschool.org.