Conjunctivitis: More than meets the eye

Conjunctivitis is commonly diagnosed in pediatric patients and is a frequent reason for exclusion from school and daycare.  For this study, investigators sought to identify specific bacterial and viral pathogens associated with a clinical diagnosis of conjunctivitis in children, and among those with the condition, determine rates of resolution by 5 days, and assess whether ophthalmic antibiotics led to a higher rate of resolution.  Conjunctival swabs were obtained on 194 outpatient children with a clinical diagnosis of conjunctivitis (cases), and 196 similar children without the diagnosis (controls).  The rate of identification of bacterial pathogens was 76% and 57%, respectively, in cases and controls, and 5 and 11%, respectively, for viruses.  Among all pathogens, only H influenzae was identified significantly more frequently in cases than in controls (62% vs.29%, P < .001).  In the children with conjunctivitis, by day 5 the condition was improved in 96% and had resolved in 85%.  The rate of improvement or resolution was not significantly higher in those treated with ophthalmic antibiotics overall, or in the subset of cases in whom H influenza had been isolated. 

Investigator’s conclusion: H influenzae was the only pathogen tested that was associated with acute conjunctivitis in children.

Commentary
Most cases of conjunctivitis are self-limited, resolving in 7-10 days without treatment with antibiotics, yet antibiotics are usually prescribed. Many factors ought to be considered when deciding whether to prescribe an antibiotic for conjunctivitis, including parent expectations, clinical presentation, school/daycare policies, and lost parenteral work hours.  Pediatric guidelines state that antibiotic treatment is not required to return to school or daycare. However, school and daycare policies vary widely.  The results of the study should serve as fuel to the fire for advocating an immediate return to school/daycare in the vast majority of cases, even in the absence of antibiotic treatment.

Bottom Line: Think twice before prescribing antibiotics for conjunctivitis.

Editors’ Note
The importance of clinical cure cannot be dismissed. The results of the current study, however, underscore our previous observation: clinical cure does not necessarily equate with bacteriologic cure. The latter was examined neither in this nor previous studies.