Acute Keratitis

exp date isn't null, but text field is

Introduction

  • Infection or inflammation of the cornea
  • It could be secondary to trauma or associated with infective conjunctivitis or occur de novo

Clinical features

  • Irritation, pain
  • Red eye (conjunctival congestion)
  • Eye discharge: watery; purulent (if bacterial)
  • Photophobia
  • Visual impairment, depending on the site and size of ulcer and if interstitial
  • Hypopion, if associated with uveitis (no hypopion if viral)
  • Ulceration of cornea, which stains with fluoresceine; no ulcer in interstitial keratitis

Aetiology

  • Exogenous
    • Marginal ulcers secondary to bacterial conjunctivitis (S. aureus)
    • Central ulcers (Pneumococcus, Herpes simplex, fungi)
  • Keratomalacia (Vitamin A deficiency)
  • Exposure (7th cranial nerve palsy or dysthyroid eye disease)
  • Endogenous
    • Interstitial keratitis of congenital syphilis
    • Interstitial keratitis of Herpes zoster

Differential diagnoses

  • Infective conjunctivitis
  • Acute iritis
  • Acute glaucoma

Complications

  • Corneal perforation
  • Corneal scarification

Investigations

  • Corneal scraping for microscopy, culture and sensitivity

Drug treatment

  • Antibiotic drops (if bacterial)
    • Chloramphenicol eye drops 5%: Apply 1 drop at least every 2 hours, and then reduce the frequency as infection is controlled and continue for 48 hours after healing
  • Atropine drops; 1 drop, twice daily
  • Antivirals (if dendritic ulcer)
    • Acyclovir; Apply 1 cm ointment 5 times daily (continue for at least 3 days after complete healing)
    • Idoxuridine 5% in dimethylsulfoxide
    • Adult and child over 12 years: apply to lesions 4 times daily for 4 days, starting at first sign of attack
    • Child under 12 years: not recommended
  • Topical steroids

Only for interstitial keratitis where there is no active ulcer

Non-drug measures

  • Lateral tarsorrhaphy for exposure keratopathy

Notable adverse drug reactions, contraindications and caution

  • Never use topical steroids in the presence of an active microbial ulcer

Prevention

  • Treat initial infection or trauma promptly to avoid progression to keratitis