Demographics: bacterial keratitis most common

Etiology:

• Bacterial infection: s. aureus, s. pneumoniae, pseudomonas aeruginosa, syphilis, enterobacteriaceae
  • Risk factors: contact lens use, recent eye surgery or injury, immunodeficiency & lacrimal duct stenosis
• Viral infection: herpes simplex keratitis (due to reactivated HSV type 1 from the trigeminal ganglion)

Clinical Features:

• Blurry vision (HSV can cause blindness)
• Photophobia
• Red eyes
• Eye pain
• Foreign body sensation
• Excessive tearing
• Specific to bacterial keratitis:
  • Purulent discharge, teary eyes