Interventions for herpes simplex virus epithelial keratitis

BACKGROUND: Many clinical trials have been performed on the acute treatment of dendritic epithelial keratitis. Surveys of antiviral pharmacology and of herpes simplex virus eye disease have evaluated different commercially available agents, but a systematic review of all comparative clinical studies has not previously been undertaken. OBJECTIVES: The objective of this review is to compare the effects of various treatments for dendritic or geographic herpes simplex virus epithelial keratitis. SEARCH STRATEGY: Sources searched for relevant studies were the Cochrane Eyes and Vision Group specialized register, The Cochrane Controlled Trials Register - CENTRAL, MEDLINE, EMBASE, Index Medicus, Excerpta Medica Ophthalmology, reference lists of primary reports, review articles, and corneal textbooks and conference proceedings pertaining to ocular virology. SELECTION CRITERIA: This review includes comparative clinical trials that assessed oral or topical ophthalmic antiviral agents, or physical or chemical debridement in people with active epithelial keratitis. DATA COLLECTION AND ANALYSIS: The reviewer extracted data and assessed trial quality. Interventions were compared by the proportions of participants healed at seven days and at fourteen days after trial enrollment. MAIN RESULTS: This review includes data from 96 trials which randomised a total of 4991 participants. Compared to idoxuridine, the topical application of vidarabine, trifluridine, or acyclovir generally resulted in a significantly greater proportion of participants healing within one week of treatment. Among these three antiviral agents, no treatment emerged as significantly better for the therapy of dendritic epithelial keratitis. Insufficient placebo-controlled studies were available to assess debridement and other physical and physicochemical methods of treatment. Interferon monotherapy had a slight beneficial effect on dendritic epithelial keratitis, but not better than other antiviral agents, and was useful with debridement. REVIEWER'S CONCLUSIONS: Currently available and investigational antiviral agents are effective and nearly equivalent, but the combination of an antiviral nucleoside and interferon seems to speed healing. Future trials of the acute treatment of herpes simplex virus epithelial keratitis must aim to achieve adequate statistical power for assessing the primary outcome and should consider the effect of lesion size and other characteristics on treatment response.