Conjunctivitis in the ED: Red Eye Rundown

-Case-

A 27-year-old woman shows up to the ED complaining of red, itchy eyes for the past 3 days. She reports watery discharge and that the symptoms started in one eye and spread to the other. No vision changes or pain are noted, and she mentions a few of her coworkers have had something similar recently. On exam, her conjunctivae are injected bilaterally with clear discharge, and there is preauricular lymphadenopathy. Her pupils are equal and reactive, and visual acuity is normal.

-Evaluation-

Conjunctivitis, also known as “pink eye,” is inflammation of the conjunctiva and is a common cause of red eye in the ED. The three main types are viral, bacterial, and allergic.

• Viral conjunctivitis is the most common form. It often starts in one eye and spreads to the other, accompanied by watery discharge, conjunctival injection, and preauricular lymphadenopathy. Adenovirus is the typical culprit and it’s highly contagious.
• Bacterial conjunctivitis is more common in children and presents with purulent discharge, eyelid crusting, and conjunctival injection. Vision is typically unaffected, and it usually starts unilaterally. It can be caused by Staph, Strep, H. flu, or Moraxella. Hyperacute bacterial conjunctivitis (from N. gonorrhoeae) is a rare but dangerous variant with copious discharge and chemosis.
• Allergic conjunctivitis is usually bilateral, with intense itching, watery discharge, and a history of allergies. It tends to be seasonal and may be accompanied by sneezing or nasal symptoms.

Red Flags:

• Decreased visual acuity
• Severe eye pain
• Photophobia
• Ciliary flush
• Corneal opacity
• Foreign body sensation
• Contact lens use (due to increased risk of pseudomonal keratitis)

These findings should prompt consideration of more serious causes of red eye (e.g., keratitis, iritis, acute angle-closure glaucoma).

-Management-

• Viral conjunctivitis: Supportive care with cold compresses and artificial tears. Strict hand hygiene and avoidance of touching the eyes to prevent spread. Most cases resolve within 1-2 weeks.
• Bacterial conjunctivitis: Empiric treatment with topical antibiotics (e.g., erythromycin ointment or polymyxin-trimethoprim drops). Fluoroquinolones may be used in contact lens wearers due to pseudomonas coverage.
• Hyperacute bacterial conjunctivitis: Immediate ophthalmology consult, hospitalization, and systemic plus topical antibiotics.
• Allergic conjunctivitis: Antihistamine or mast cell stabilizer eye drops (e.g., olopatadine), cool compresses, and avoidance of allergens.

-Fast Facts-

• Viral conjunctivitis is highly contagious – think coworker clusters and daycare outbreaks.
• If there’s a red eye and vision change, it’s not just conjunctivitis until proven otherwise.
• Contact lens users with eye redness deserve a different workup.
• Don’t forget to flip the lid if foreign body sensation is reported.

A red eye may be benign, but not always. Conjunctivitis is usually self-limited, but knowing when to treat, when to isolate, and when to worry is key in the ED.

-References-

1. Azari AA, Barney NP. Conjunctivitis: A systematic review of diagnosis and treatment. JAMA. 2013;310(16):1721-1729. doi:10.1001/jama.2013.280318
2. Sheikh A, Hurwitz B. Topical antibiotics for acute bacterial conjunctivitis: Cochrane systematic review and meta-analysis update. Br J Gen Pract. 2005;55(521):962-964.
3. Kuo IC. Bacterial conjunctivitis. BMJ Clin Evid. 2015;2015:0704.
4. Udeh BL, Schneider JE, Ohsfeldt RL. Cost effectiveness of olopatadine for allergic conjunctivitis. Curr Med Res Opin. 2008;24(10):2729-2735.
5. Rose PW, Harnden A, Brueggemann AB, et al. Chloramphenicol treatment for acute infective conjunctivitis in children in primary care: a randomized double-blind placebo-controlled trial. Lancet. 2005;366(9479):37-43. doi:10.1016/S0140-6736(05)66585-X