METHODS: Totally 89 patients(89 eyes)with chronic infective keratitis were diagnosed in our hospital from January 2015 to December 2017 were selected as the research objects and the cause of the disease and pathogenic characteristics of different age groups, including 13-32 years group(35 eyes in 35 patiens), 33-52 years group(28 eyes in 28 patiens)and 53-73 years group(26 eyes in 26 patiens), were retrospectively studied.

RESULTS: There were no significant differences in the etiological distribution of patients in the three groups(P=0.290). There was no significant difference in the distribution of microbial composition among the three groups(χ²=0.258, P=1.000). The incidence of chronic infectious keratitis caused by fungal infection in the three groups was higher than that of other pathogenic microbes. In this study, 26 cases were positive in bacterial culture, including Staphylococcus epidermidis(50%), Pseudomonas aeruginosa(15%), Streptococcus salivarius(12%), Streptococcus pneumoniae(8%), Escherichia coli(8%)and Neisseria gonorrhoeae(8%). Pseudomonas aeruginosa and Staphylococcus epidermidis were the common bacterial strains in the positive culture results. In the cultivation of fungal strains 24 were positive cultures including Fusarium(46%), Aspergillus(17%), Alternaria(21%), Mycelium(no spore,4%), Penicillium(4%)and Curvularia(8%). Two strains of Fusarium spp. and Alternaria spp. were high of all patients.

CONCLUSION: There were no significant differences in the etiology of infectious keratitis among different age groups. Fungal infection is the main pathogen in the distribution of pathogens, the bacteria were mainly Streptococcus epidermidis in etiological features but in fungi, Fusarium dominates. So early prevention and prevention of infective keratitis should be strengthened and early treatment should be given.