What is the treatment for infectious conjunctivitis?

Treatment of Infectious Conjunctivitis

For infectious conjunctivitis, a 5-7 day course of broad-spectrum topical antibiotics applied 4 times daily is the recommended first-line treatment, with fluoroquinolones such as moxifloxacin being effective against common pathogens including various bacterial species. 1, 2, 3

Diagnosis and Assessment

• Bacterial conjunctivitis typically presents with marked inflammation, purulent discharge, and sometimes pain 1
• Consider obtaining conjunctival cultures and Gram staining before initiating treatment, especially in moderate to severe cases 1, 3
• Examine for swollen preauricular or submandibular lymph nodes, which may indicate bacterial infection 1

Treatment Based on Type and Severity

Viral Conjunctivitis

• Most cases are self-limiting and require only supportive care 4
• For herpes simplex virus conjunctivitis, topical antivirals may be beneficial 4
• For varicella zoster virus conjunctivitis:
  • Topical antibiotics are recommended to prevent secondary bacterial infection 4
  • Oral antivirals may be beneficial for persistent or recalcitrant disease (acyclovir 800 mg five times daily, valacyclovir 1000 mg every 8 hours, or famciclovir 500 mg three times daily for 7 days) 4

Bacterial Conjunctivitis

• Mild bacterial conjunctivitis:

  • Often self-limited but treatment with topical antibiotics accelerates clinical and microbiological remission 4, 2
  • A 5-7 day course of broad-spectrum topical antibiotic applied 4 times daily is recommended 1, 2, 3
  • Fluoroquinolones (e.g., moxifloxacin, gatifloxacin) are effective against common pathogens 1, 5
  • Aminoglycosides like tobramycin are also effective options 1, 3

• Moderate to severe bacterial conjunctivitis:

  • Characterized by copious purulent discharge, pain, and marked inflammation 2, 3
  • Obtain conjunctival cultures and Gram staining before initiating treatment 1, 3
  • More aggressive treatment approach may be needed 2

Special Cases

• Gonococcal conjunctivitis:

  • Requires systemic antibiotic therapy rather than topical treatment alone 2, 3
  • Daily follow-up until resolution 2
  • Topical treatment as for bacterial keratitis if corneal involvement is present 2

• Chlamydial conjunctivitis:

  • Requires systemic therapy, especially in infants 2, 3
  • Follow-up evaluation is important as treatment failure can occur in up to 19% of cases 2

• Molluscum contagiosum:

  • Treatment to remove lesions is indicated in symptomatic patients 4
  • Options include incision and curettage, simple excision, excision and cautery, and cryotherapy 4

Specific Antibiotic Options

• Fluoroquinolones (e.g., moxifloxacin 0.5%): Instill one drop in the affected eye 3 times a day for 7 days 5

  • Effective against: Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Haemophilus influenzae, Chlamydia trachomatis, and other common pathogens 5

• Aminoglycosides (e.g., tobramycin): Effective against many common bacterial pathogens 1, 3

• Alternative option: Povidone-iodine 1.25% ophthalmic solution may be as effective as topical antibiotics and could be considered when access to antibiotics is limited 2, 3

Follow-up Recommendations

• Return for follow-up if no improvement is seen after 3-4 days of treatment 1, 3
• Follow-up should include interval history, visual acuity measurement, and slit-lamp biomicroscopy 4, 1
• Schedule follow-up within 1 week for severe cases with corneal involvement or membranous conjunctivitis 1

Important Considerations and Pitfalls

• Avoid using topical corticosteroids unless under close supervision, as they may prolong bacterial shedding and worsen infection 1
• Increasing bacterial resistance is a concern, particularly with methicillin-resistant S. aureus (MRSA) 2, 3
• For children with gonococcal or chlamydial infections, consider the possibility of sexual abuse 2
• Advise patients about hygiene measures to prevent spread, such as frequent hand washing and avoiding sharing of personal items 1
• Patients should be advised not to wear contact lenses if they have signs or symptoms of bacterial conjunctivitis 5

When to Refer to an Ophthalmologist

• Visual loss, moderate or severe pain, severe purulent discharge 3
• Corneal involvement, conjunctival scarring 3
• Lack of response to therapy or recurrent episodes 3
• Neonates require prompt consultation with the pediatrician or primary care physician, especially for HSV infection which can be life-threatening 4