Type	Characteristic features	Therapy
Bacterial keratitis	• Most common form of keratitis • ↑ Risk with wearing contact lenses • Purulent discharge and/or hypopyon • Round corneal infiltrate or ulcer	• Topical broad-spectrum antibiotics (e.g., ciprofloxacin)
Herpes zoster keratitis	• ↓ Corneal sensation • Punctate lesions on the corneal surface (early disease) • Vesicular eruption on forehead, bridge, and tip of the nose	• Oral acyclovir, valacyclovir, or famciclovir • Topical steroids
Herpes simplex keratitis	• Dendritic or geographic corneal ulcer	• Topical trifluridine or ganciclovir
Acanthamoeba keratitis	• ↑ Risk with wearing contact lenses • Corneal ring infiltrate	• Topical antiseptic (e.g., chlorhexidine) with propamidine