Prognosis of clinical treatment for fungal keratitis and its influence factors

Abstract

Background Fungal keratitis has poor prognosis and high blinding rate, so it is vital to identify the risk factors that affect the treating outcome and prognosis of fungal keratitis. Objective This study was to evaluate the clinical outcome of fungal keratitis and identify the affecting factors. Methods This was a series cases-observational study.A total of 267 eyes of 267 patients with fungal keratitis were included in Henan Eye Institute during January 2013 to January 2014.Eye examinations were performed including slit-lamp microscope examination, corneal smears, confocal microscopy, fungal culture and identification.Combined anti-fungal drugs were topically used in all eyes for the initial treatment then the treating regimen were selected based on the susceptibility testing.corneal lesion resection combined with conjunctival flap transplantation, lamellar corneal transplantation or penetrating corneal transplantation was performed respectively on the patients with poor curative effect after drug treatment.The clinical prognosis of the patients was graded and the affecting factors for clinical outcome were evaluated.This study protocol complied with Helsinki Declaration and was approved by Ethic Committee of Henan Eye Hospital.Written informed consent was obtained from patients or guardians. Results One hundred and eighty-five eyes were cured by anti-fungal eye drops with the effective rate of 69.29%, and the inflammation was controlled in 60 eyes who received combination procedure of anti-fungal drugs with different surgeries, while 22 eyes lost visual function because of refractory glaucoma and final evisceration.The total clinical effective rate was 91.76%.Aspergillus and Fusarium spp. appeared to be the most common pathogenic fungi by drug sensitivity test.The keratitis caused by Aspergillus had lowest cure rate among different fungi (χ2=11.350, P=0.002) and the most poor clinical prognosis (H=31.285, P=0.013). The medication curative rate was 71.8% in the patients with positive culture outcome, which was higher than 62.5% in the patients with negative culture outcome (χ2=8.75, P<0.01). A significant difference was found in the medication curative rate and prognosis between the patients with ≥2 kinds of sensitive anti-fungal drugs and the patients with <2 kinds of sensitive anti-fungal drugs (77.5% versus 52.3%, χ2=9.63, P<0.01; H=24.281, P=0.021). Size of infiltration area, with or without hypopyon, number of sensitive drugs, and pathogenic fungi were significantly correlated with clinical outcome(all at P<0.05). Conclusions In vitro susceptibility testing can guide clinical drug treatment of fungal keratitis.Infiltration area >16 mm2, hypopyon >2 mm, resistance to those drugs in vitro and infection of Fusarium.spp or Aspergillus.spp are predictors of a poor outcome. Key words: Eye infections, fungal/therapy; Keratitis, fungal, Treatment outcome; Risk factors; Human