Keratomycosis caused by Aspergillus viridinutans: an Aspergillus fumigatus-resembling mold presenting distinct clinical and antifungal susceptibility patterns

We report here a case of fungal keratitis caused by Aspergillus viridinutans, a member of the genus which was found to have clinical and antifungal susceptibility characteristics distinct from the species it most closely resembles, Aspergillus fumigatus. A 26-year-old woman presented with contact lens-associated keratitis, the etiologic agent of which was initially slow growing and found to be resistant to amphotericin B and voriconazole. Therapeutic keratoplasty was performed and an isolate from a corneal scraping was identified as A. viridinutans through partial DNA sequencing of the β-tubulin gene, along with its slow growth 42°C. In contrast with A. fumigatus, A. viridinutans proved to be resistant to a wider variety of antifungal agents. To the best of our knowledge, this is the first case of keratitis caused by A. viridinutans. Clinical isolates of the genus Aspergillus include rarely encountered species such as A. viridinutans. These species may show clinical manifestations distinct from those of A. fumigatus, including clinical resistance to amphotericin B and voriconazole and relatively low susceptibility to other antifungal agents.