Introduction
Acute Keratitis is an infection or inflammation of the cornea.
It could be secondary to trauma to the cornea and is sometimes associated with infective conjunctivitis but could 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 fluorescene; 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
Investigation
Corneal scraping for microscopy, culture and sensitivity
Drug treatment
Antibiotic drops (if bacterial)
Chloramphenicol eye drops 0.5%
- 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 2 times daily
Antivirals (if dendritic ulcer)
Conjunctiva,
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
Caution and contraindications to treatment
- Never use topical steroids in the presence of an active ulcer
Prevention
- Treat initial infection or trauma promptly to avoid progression to keratitis