How do you differentiate and treat bacterial vs viral conjunctivitis?

Differentiation and Treatment of Bacterial vs Viral Conjunctivitis

Bacterial and viral conjunctivitis have distinct clinical presentations that guide appropriate treatment, with bacterial conjunctivitis typically presenting with purulent discharge and matted eyelids, while viral conjunctivitis presents with watery discharge and often follows upper respiratory infection. 1

Clinical Differentiation

Bacterial Conjunctivitis

• Key Distinguishing Features:
  • Mucopurulent discharge (yellow-green)
  • Mattering and adherence of eyelids on waking
  • Absence of itching
  • More common in children
  • Usually bilateral but may start unilaterally
  • Minimal pain

Viral Conjunctivitis

• Key Distinguishing Features:
  • Watery/serous discharge
  • Follicular reaction on palpebral conjunctiva
  • Preauricular lymphadenopathy
  • Often follows upper respiratory infection
  • Highly contagious (adenovirus causes ~80% of cases)
  • May have subconjunctival hemorrhage

Treatment Approach

Bacterial Conjunctivitis

• Treatment Options:

  • Most uncomplicated cases resolve in 1-2 weeks without treatment 2
  • Topical antibiotics hasten clinical and microbiological remission 1
  • Common antibiotics include fluoroquinolones, aminoglycosides, and macrolides
  • Delayed antibiotic prescribing has similar outcomes to immediate prescribing 3

• Special Considerations:

  • Contact lens wearers require antibiotic treatment even for mild cases due to risk of Pseudomonas infection 1
  • Gonococcal conjunctivitis requires systemic antibiotics (ceftriaxone 1g IM single dose) plus ocular lavage 1
  • Chlamydial conjunctivitis requires oral azithromycin 1g single dose or doxycycline 100mg BID for 7 days 1

Viral Conjunctivitis

• Treatment Options:

  • Primarily supportive care as antibiotics are ineffective 1
  • Artificial tears for lubrication
  • Cold compresses for symptomatic relief
  • Antihistamine eye drops may reduce irritation
  • Strict hand hygiene to prevent transmission

• Special Considerations:

  • Herpes simplex conjunctivitis requires antiviral treatment (topical or oral acyclovir) 1
  • Avoid corticosteroids in undiagnosed viral conjunctivitis, especially if herpes is suspected 4

Prevention of Transmission

• Frequent handwashing
• Avoid touching or rubbing eyes
• Use separate towels and pillows
• Proper disinfection of surfaces and equipment
• Patients should avoid close contact with others during contagious period 1

Red Flags Requiring Immediate Referral

• Severe pain
• Sudden vision loss
• Significant purulent discharge
• Corneal involvement
• Lack of response to therapy
• History of HSV eye disease
• Immunocompromised patients
• Neonatal conjunctivitis (requires immediate evaluation) 1, 3

Common Pitfalls to Avoid

1. Indiscriminate use of antibiotics for viral conjunctivitis (ineffective and contributes to resistance) 5
2. Using corticosteroids without ruling out herpes infection (can worsen condition) 4
3. Inadequate hygiene instructions leading to spread of infection
4. Failure to recognize sight-threatening conditions requiring urgent referral
5. Overlooking underlying systemic conditions that may present with conjunctivitis (e.g., thyroid disorders, STIs) 5

Remember that proper diagnosis based on clinical features is crucial for appropriate management, as no single sign or symptom perfectly differentiates bacterial from viral conjunctivitis 3.