Conjunctivitis, Acute

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  • Inflammation of the bulbar and/or palpebral conjunctiva of <4 weeks’ duration
  • System(s) affected: nervous, skin/exocrine
  • Synonym(s): pink eye
Geriatric Considerations
  • Suspect autoimmune, systemic, or irritative process.
  • If purulent, risk of bacterial cause increases with age, with age >65 years and bilateral lid adherence risk for bacterial infection is >70%.
Pediatric Considerations
  • Neonatal conjunctivitis may be gonococcal, chlamydial, irritative, or related to dacryocystitis.
  • Pediatric ER study; 78% positive bacterial culture, mostly Haemophilus influenzae; 13% no growth; other studies showed >50% adenovirus.
  • Children <5 years 7 times more likely have bacterial involvement than older children or mid aged adults.
  • Despite lack of evidence, daycare regulations may require a child with presumed conjunctivitis to be treated with a topical antibiotic before returning (1)[A].


  • Predominant age
    • Pediatric: viral, bacterial
    • Adult: viral, bacterial, allergic
  • Predominant sex: male = female

1–2% of ambulatory office visits, up to 3% of ER visits

Etiology and Pathophysiology

  • Viral
    • Adenovirus (common cold), coxsackievirus (implicated in recent hemorrhagic conjunctivitis epidemics in Asia and Middle East)
    • Enterovirus (acute hemorrhagic conjunctivitis)
    • Herpes simplex
    • Herpes zoster or varicella
    • Measles, mumps, or influenza
  • Bacterial
    • Staphylococcus aureus or Staphylococcus epidermidis
    • Streptococcus pneumoniae
    • H. influenzae (children)
    • Pseudomonas spp. or anaerobes (contact lens users)
    • Acanthamoeba-contaminated contact lens solution may cause keratitis (rare; ~30 cases per year in United States).
    • Neisseria gonorrhoeae and Neisseria meningitidis
    • Chlamydia trachomatis: gradual onset 1 to 4 weeks
    • Escherichia coli neonatal conjunctivitis reported rarely, and tuberculosis reported in treatment resistant cases
  • Allergic
    • Hay fever, seasonal allergies, atopy
  • Nonspecific
    • Irritative: topical medications, wind, dry eye, UV light exposure, smoke
    • Autoimmune: Sjögren syndrome, pemphigoid, Wegener granulomatosis
    • Rare: Rickettsia, fungal, parasitic, tuberculosis, syphilis, Kawasaki disease, chikungunya, Graves disease, gout, carcinoid, sarcoid, psoriasis, Stevens-Johnson syndrome, Reiter syndrome

Risk Factors

  • History of contact with infected persons
  • Sexually transmitted disease (STD) contact: gonococcal, chlamydial, syphilis, or herpes
  • Contact lenses: pseudomonal or acanthamoeba keratitis
  • Epidemic bacterial (streptococcal) conjunctivitis reported in school settings

General Prevention

  • Wash hands frequently.
  • Eyedropper technique: while eye is closed and head back, several drops over nasal canthus and then open eyes to allow liquid to enter. Never touch tip of dropper to skin or eye.

Commonly Associated Conditions

  • Viral infection (e.g., common cold)
  • Possible sexually transmitted infection

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