What is the treatment for Keratitis (inflammation of the cornea)?

Treatment of Keratitis (Inflammation of the Cornea)

The first-line treatment for bacterial keratitis is topical antibiotics, with fluoroquinolones being as effective as combination therapy for most cases, while severe or central keratitis requires more aggressive treatment with loading doses followed by hourly application. 1, 2

Diagnosis and Assessment

• Careful history should include ocular symptoms (pain, redness, discharge, blurred vision, photophobia), contact lens history, previous ocular conditions, and medical problems 1
• Visual acuity should be documented as a baseline, though patient discomfort and inflammation may compromise measurement 1
• Examination should focus on corneal infiltrates, epithelial defects, stromal involvement, anterior chamber inflammation, and presence of hypopyon 1
• Fluorescein staining is essential to identify epithelial defects and distinguish from pooling in areas of corneal thinning 1, 2

Culture and Laboratory Testing

• Smears and cultures are recommended before starting antibiotics in cases with:
  • Central, large corneal infiltrates (≥2mm in size and within 3mm of corneal center)
  • Significant stromal involvement or melting
  • Anterior chamber inflammation (≥1+ cells)
  • History of corneal surgery
  • Atypical features suggesting fungal, amoebic, or mycobacterial keratitis
  • Multiple corneal infiltrates 1
• Gram stain, Giemsa stain, and culture are essential for severe, central, or sight-threatening cases 1

Initial Treatment Approach

• For small, peripheral bacterial keratitis:

  • Single-drug therapy with a fluoroquinolone is as effective as combination therapy 1, 2
  • Treatment can be administered on an outpatient basis 1

• For central or severe keratitis (deep stromal involvement or infiltrate >2mm with suppuration):

  • Begin with loading dose every 5-15 minutes followed by hourly application 1, 2
  • Consider fortified antibiotics (vancomycin for gram-positive, tobramycin for gram-negative coverage) 3
  • Cycloplegic agents may be used to decrease pain and prevent synechiae formation 1

• For viral keratitis (herpes simplex dendritic ulcers):

  • Ganciclovir ophthalmic gel 0.15% applied 5 times daily until ulcer heals, then 3 times daily for 7 days 4

• For fungal keratitis:

  • Natamycin ophthalmic suspension 5% is indicated for treatment 5

Monitoring and Follow-up

• Clinical response is judged by:

  • Reduced pain and discharge
  • Lessened eyelid edema or conjunctival injection
  • Consolidation and sharper demarcation of stromal infiltrate
  • Decreased density of infiltrate without progressive stromal loss
  • Reduced anterior chamber inflammation
  • Initial re-epithelialization
  • Cessation of progressive corneal thinning 1

• Daily follow-up is recommended until clinical improvement is noted for severe infections 2

• Lack of improvement within 48 hours suggests need to modify therapy 1

Adjunctive Therapies

• Corneal cross-linking may be beneficial in cases refractory to medical therapy or to prevent corneal melting, especially for anterior infections 1, 6
• For persistent epithelial defects with controlled infection, consider:
  • Lubrication
  • Antibiotic ointment
  • Bandage contact lens (with caution and continued antibiotic coverage)
  • Amniotic membrane coverage
  • Tarsorrhaphy 1

Special Considerations

• Contact lens wearers should discontinue lens use immediately due to higher risk of Pseudomonas infection 2
• Avoid bandage contact lens for traumatic abrasions in contact lens wearers 2
• Corticosteroids should be reduced or eliminated until infection is controlled 1
• Hospitalization may be necessary if keratitis is severe, vision-threatening, compliance is unlikely, or pain is severe 1

Prevention

• Educate patients with risk factors about signs requiring prompt consultation 2
• Treat underlying ocular surface disease such as corneal epithelial defects, tear deficiency, entropion, or lagophthalmos 1
• For contact lens wearers, emphasize proper lens hygiene and avoid overnight wear 1, 2
• Consider daily disposable lenses which have lower complication rates than reusable lenses 1

Complications and Prognosis

• Untreated or severe bacterial keratitis may result in corneal perforation, endophthalmitis, and loss of the eye 1
• Central or paracentral infections can cause substantial visual loss even after successful treatment 1
• Vision impairment from corneal scarring may require visual rehabilitation or corneal transplantation 7