Identification of Fusarium solani as the prevalent strain in fungal keratitis / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the etiological and epidemiological characteristics of fungal keratitis in Jilin province of China and to establish a rapid and specific method for molecular identification of the prevalent fungal pathogens.Methods Corneal scrapings were collected from 225 patients with suspected fungal keratitis.Fungal strains were isolated and identified based on their morphology and physiological characteristics.The epidemiological characteristics of all isolated strains causing fungal keratitis were statistically analyzed.Species-specific primers of Fusarium solani (F.solani) were designed and used together with the universal fungal primers to establish a multiplex PCR assay for identification of F.solani in corneal scrapings.Results 156 out of 225 patients (69.3％) were diagnosed as fungal keratitis by fungal culture followed by the examination of morphological and physiological characteristics.A total of 168 pathogenic fungi strains were isolated,most of which were Fasarium spp.(49.4％),followed by Aspergillus spp.(17.9％) and Candida spp.(14.3％).F.solani was the predominant pathogen accounting for 34.5％ in all patients.Most of the patients (87.5％) were farmer and male patients (57.1％) accounted for the majority of 156 patients as well.Corneal trauma (38.5％) was considered as the main predisposing factor.The established multiplex PCR could specifically amplify a 300 bp nucleotide fragment of F.solani.It could be used for a rapid identification of F.solani in corneal scrapings.Conclusion Fusarium genus,particularly the species of F.solani,was the predominant pathogen for fungal keratitis in Jilin province of China.Corneal trauma was the most important predisposing factor.The established multiplex PCR could identify fungal infection from corneal scrapings rapidly and specifically.These findings are very important for the early diagnosis and treatment of fungal keratitis.