Topical antibiotics for the management of bacterial keratitis: an evidence-based review of high quality randomised controlled trials

Background Severe bacterial keratitis (BK) typically requires intensive antimicrobial therapy. Empiric therapy is usually with a topical fluoroquinolone or fortified aminoglycoside-cephalosporin combination. Trials to date have not reached any consensus as to which antibiotic regimen most effectively treats BK. Methods A systematic review and meta-analysis using Cochrane methodology was undertaken to evaluate the effectiveness of topical antibiotics in the management of BK. Outcomes included treatment success, time to cure, serious complications of infection and adverse effects. Results A comprehensive search for trials resulted in 27 956 abstracts for review. This eventually resulted in 16 high quality trials involving 1823 participants included in the review. Treatment success, time to cure and serious complications of infection were comparable among all antibiotic treatments included in the review. Furthermore, there was no evidence of difference in the risk of corneal perforation with any included antibiotics or antibiotic classes. Fluoroquinolones significantly reduced risk of ocular discomfort and chemical conjunctivitis but increased the risk of white precipitate formation compared with aminoglycoside-cephalosporin. Fortified tobramycin-cefazolin was approximately three times more likely to cause ocular discomfort than other topical antibiotics. Conclusions Results of this review suggest no evidence of difference in comparative effectiveness between fluoroquinolones and aminoglycoside-cephalosporin treatment options in the management of BK. There were differences in safety profile, however. Fluoroquinolones decreased the risk of ocular discomfort and chemical conjunctivitis while ciprofloxacin increased the risk of white corneal precipitate compared with aminoglycoside-cephalosporin.