An Unusual Case of Mycotic Keratitis due to Neoscytalidium dimidiatum in an Agriculturist from Karnataka, India

Document Type : Case Report

Authors
A. A. Ashraf 1
P. Bhat U. 2
A. M. Anil 3
F. S. Seythin Akath 3
1 Assistant Professor, Nitte (Deemed to be University), KS Hegde Medical Academy (KSHEMA), Department of Microbiology, Mangalore, Karnataka, India.
2 Associate Professor, Nitte (Deemed to be University), KS Hegde Medical Academy (KSHEMA), Department of Microbiology, Mangalore, Karnataka, India.
3 Junior Resident, Nitte (Deemed to be University), KS Hegde Medical Academy (KSHEMA), Department of Microbiology, Mangalore, Karnataka, India.
10.52547/iem.10.2.153
Abstract
Background: There are few keratitis cases caused by the plant pathogen Neoscytalidium dimidiatum, which is known to cause skin and nail infections in humans. This fungus primarily affects immunocompromised patients; however, cases have rarely been reported in immunocompetent individuals. In this case report, we present an uncommon case of N. dimidiatum keratitis in an immunocompetent Indian male patient with no significant co-morbidities, admitted to Justice K.S. Hegde Charitable hospital in Mangaluru, India.

Materials & Methods: The patient underwent corneal scraping, and a sample was sent for further microbiological evaluation. KOH (potassium hydroxide) mount of corneal scrapings was performed. Additionally, corneal scrapings were inoculated on Sabouraud dextrose agar (SDA), with and without cycloheximide, as well as blood agar (BA). Slide culture was conducted to observe fungal growth on SDA without cycloheximide. Subsequently, lactophenol cotton blue (LPCB) mount of the fungal colony isolated from the aforementioned slide culture was performed.

Findings: KOH mount of corneal scrapings revealed septate fungal hyphae, while fungal culture showed grey-to-brown colonies with black pigmentation on the reverse after ten days of incubation at room temperature. Chains of arthroconidia, typical of Neoscytalidium species, were observed upon staining with lactophenol cotton blue mount of the fungal colony isolated from the slide culture. The patient was clinically managed with debridement and ophthalmic antifungal agent.

Conclusion: N. dimidiatum cases could also occur in immunocompetent individuals. Therefore, prompt diagnosis and vigorous antifungal therapy are critical for effective recovery and prevention of severe ocular complications.

Keywords

Subjects

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Infection Epidemiology and Microbiology
Volume 10, Issue 2
June 2024
Pages 153-156