Antibiotics versus placebo for acute bacterial conjunctivitis

Abstract

BACKGROUND: There are concerns regarding whether antibiotic therapy confers significant benefit in the treatment of acute bacterial conjunctivitis.OBJECTIVES: The aim of this review is to assess the benefit and harm of antibiotic therapy in the management of acute bacterial conjunctivitis.SEARCH STRATEGY: We searched the Cochrane Eyes and Vision Group specialised register, the Cochrane Controlled Trials Register - Central, MEDLINE and the reference lists of identified trial reports. We used the Science Citation Index to look for articles that cited the relevant studies, and we contacted investigators and pharmaceutical companies for information about additional trials. The most recent searches were carried out in September 1998.SELECTION CRITERIA: We included double masked randomised controlled trials in which any form of antibiotic treatment had been compared with placebo in the management of acute bacterial conjunctivitis. This included topical, systemic and combination (for example, antibiotics and steroids) antibiotic usage.DATA COLLECTION AND ANALYSIS: One reviewer extracted data and the accuracy was checked by a second reviewer. Relative risks were summarised. We tested for heterogeneity between studies.MAIN RESULTS: Six published trials were identified of which three fulfilled the eligibility criteria for inclusion in this review. One trial was single masked and therefore excluded. A second report, when translated, was found to have no placebo group and was therefore excluded. One trial is currently 'awaiting assessment'. This has been published in abstract form and has yet to be fully reported. All the trials thus far identified appear to have been conducted on a selected specialist care patient population. The trials were heterogeneous in terms of their inclusion and exclusion criteria, the nature of the intervention, and the outcome measures assessed. Meta-analysis indicates that acute bacterial conjunctivitis is frequently a self-limiting condition, as clinical remission (cure or significant improvement) occurred by days two to five in 64% (95% confidence interval (CI) 57% to 71%) of those treated with placebo. Treatment with antibiotics was, however, associated with significantly better rates of clinical remission (days two to five: relative risk (RR) 1.31 95% CI 1.11 to 1.55, NNT=5) with a suggestion that this benefit was maintained for late clinical remission (days six to 10: RR 1.27 95% CI 1.00 to 1.61, NNT=5). Antibiotic treatment was associated with rates of microbiological remission (pathogen eradication or reduction). No serious outcomes were reported in either the active or placebo arms of these trials, indicating that important sight-threatening complications are an infrequent occurrence.REVIEWER'S CONCLUSIONS: Acute bacterial conjunctivitis is frequently a self-limiting condition but the use of antibiotics is associated with significantly improved rates of early clinical remission and early and late microbiological remission. Since trials to-date have been conducted in selected specialist care patient populations these results may not necessarily be generalisable to a primary care based population. A trial based in primary care designed to assess the cost-effectiveness of commonly prescribed antibiotic(s) versus placebo in acute bacterial conjunctivitis is warranted.