Pseudopithomyces Maydicus and Phialophora Chinensis Rare Fungal Keratitis: Case Series, DNA Sequencing, Antifungal Susceptibility Patterns

Ocul Immunol Inflamm. 2024 Jan 22:1-5. doi: 10.1080/09273948.2024.2303352. Online ahead of print.

Abstract

Purpose: We report two cases of fungal keratitis due to rare melanized fungal pathogens in ocular infection, one is the first case report of keratitis due to Pseudopithomyces maydicus and the second is keratitis due to rare fungal pathogen in ocular infections Phialophora chinensis.

Method: Conventional mycology during routine diagnostics helped in identifying these rare fungal isolates, following which we proceeded for the confirmation of identification by DNA sequencing and did in-vitro antifungal susceptibility test to understand their susceptibility pattern. The clinical information for these two patients were collected from hospital electronic medical records.

Results: We discuss the clinical presentation, treatment given, and clinical outcome in these patients and correlate these with the conventional microbiology and sequencing techniques, which helped in identifying the pathogen and the in-vitro antifungal susceptibility of these rare isolates. We also do a brief literature review for these two rare fungal pathogens.

Conclusions: Pseudopithomyces maydicus and Phialophora chinensis are rare causes of fungal keratitis due to melanized fungi. Both of this fungal keratitis respond well to medical therapy alone if diagnosed and treated early.

Keywords: Antifungal susceptibility; Phialophora chinensis; Pseudopithomyces maydicus; fungal DNA sequencing; fungal keratitis.