conjunctivitis

Last edited 10/2022 and last reviewed 10/2022

Inflammation of the conjunctiva is commonly infective or allergic. It is usually unilateral.

• it is the commonest cause of red eye (1)
• conjunctivitis in children is predominantly bacterial, with nontypeable H. influenzae being the most common organism (2)

Clinical features depend on the underlying cause

• however, the eyes often feel gritty or in allergic conjunctivitis, itchy
• discharge is a constant finding and may be purulent, mucoid or watery; typically, the eyelashes are stuck together on waking
• may be transient blurring as a consequence of discharge smearing the cornea but this is easily cleared by blinking
• photophobia and pain indicate corneal involvement - keratoconjunctivitis - which is not infrequent
• diffuse hyperaemia overlying the sclera and the inner surface of the eyelids.
• viral infection is associated with follicles; allergies, with chemosis.

Itching suggests an allergic cause (3).

Infective conjunctivitis is treated with topical antibiotics; non-infective with anti-inflammatory agents.

• a meta-analysis concluded that '..acute conjunctivitis seen in primary care can be thought of as a self-limiting condition, with most patients getting better regardless of antibiotic therapy. Patients with purulent discharge or a mild severity of red eye may have a small benefit from antibiotics...' (4)
• in randomized clinical trial and systematic review and meta-analysis (5)
  • topical antibiotics were associated with significantly shorter durations of conjunctival symptoms in children with acute infective conjunctivitis
    • RCT (n=88), moxifloxacin eye drops reduced time to clinical cure vs placebo (3.8 vs 5.7 days; p=0.04) & in meta-analysis (4 studies;n=584), topical antibiotics reduced proportion of children with symptoms of conjunctivitis on days 3 to 6 vs placebo (OR 0.59;95% CI,0.39-0.91)
    • study authors concluded that
      • findings suggest that topical antibiotic therapy should be considered for acute infective conjunctivitis in children because antibiotics were associated with significantly shorter recovery times

Reference:

1. Leibowitz HM. The Red Eye Leibowitz HM. NEJM 2000; 343:345.
2. Patel PB et al. Clinical features of bacterial conjunctivitis in children. Acad Emerg Med. 2007 Jan;14(1):1-5.
3. Rietveld RP et al. Predicting bacterial cause in infectious conjunctivitis: cohort study on informativeness of combinations of signs and symptoms. BMJ 2004 329: 206-210.
4. Jefferis Jet al. Acute infective conjunctivitis in primary care: who needs antibiotics? An individual patient data meta-analysis. Br J Gen Pract. 2011 Sep;61(590):e542-8. doi: 10.3399/bjgp11X593811.
5. Honkila M, Koskela U, Kontiokari T, et al. Effect of Topical Antibiotics on Duration of Acute Infective Conjunctivitis in Children: A Randomized Clinical Trial and a Systematic Review and Meta-analysis. JAMA Netw Open. 2022;5(10):e2234459. doi:10.1001/jamanetworkopen.2022.34459