Identification and Characterization of Fusarium proliferatum, a New Species of Fungi that Cause Fungal Keratitis

Shengtao Sun,Siyu He,Junjie Zhang,Liya Wang,Hongmin Zhang,Xiaohui Liu,Qiufei Ma,Xiaohua Li,Qixue Lui,Lei Han

doi:10.1038/s41598-018-23255-z

Abstract

Fusarium proliferatum (F. proliferatum) is known as a pathogen of corn and other crops, but its role in fungal keratitis has not been well investigated. Among 877 Fusarium isolates, we identified 155 (17.7%) stains as F. proliferatum according to their morphological features and partial DNA sequencing of translation elongation factor-1alpha (EF-1alpha ) in this study. In vitro antifungal susceptibility tests showed that the F. proliferatum strains were sensitive to natamycin and vorionazole but resistant to amphotericin B, fluconazol, ketoconazole and itaconazole. Most of the F. proliferatum-positive keratitis patients (44/155,28.4%) were aged 51–60 years old. The main cause of infection was injury by a plant (51/155, 32.9%). A combination of 1% amphotericin B and 3% ketoconazole cured 45.2% (14/31) and a combination of 0.5% natamycin and 0.5% voriconazole cured 59.1% (13/22) of F. proliferatum-positive patients. The date suggests that F. proliferatum identified through EF-1ɑ DNA sequencing is an important new species that causes fungal keratitis. Based on antifungal susceptibility, treatment with a combination of 0.5% natamycin and 0.5% voriconazole improves the therapeutic efficacy in F. prolifertum-positive patients.

Highlights

F. proliferatum (Matsush.) Nirenberg, formerly Gerlach & Nirenberg 1982, is a fungus with a worldwide distribution that has been associated with a variety of diseases in important economical plants, including corn and bananas[4,5]
Among the 2197 strains of Fusarium spp. isolated from corneas in the Henan Eye Institute during 2005–2016, 891 strains were tested for the elongation factor-1α (EF-1α) gene using DNA sequencing
The results showed that while F. proliferatum is sensitive to natamycin and vorionazole, all of the F. proliferatum samples were resistant to terbinafine, amphotericin B, fluconazol, ketoconazole and itraconazole

Summary

Introduction

F. proliferatum (Matsush.) Nirenberg, formerly Gerlach & Nirenberg 1982, is a fungus with a worldwide distribution that has been associated with a variety of diseases in important economical plants, including corn and bananas[4,5]. It can cause a disseminated infection in immunocompromised patients[6,7,8,9,10] and abscesses in the body where trauma is caused by a plant[11,12]. We evaluate the in vitro susceptibility of F. proliferatum to antifungal agents and describe the clinical features and results of treatment in F. proliferatum-positive keratitis patients

Methods

Results

Conclusion