Prevalence of Scedosporium keratitis in a rural tertiary care hospital

Abstract

Aim: To study the prevalence of Scedosporium in fungal keratitis infection from a rural tertiary care hospital. Method: Corneal scraping samples from October 2018 to October 2019 had come to Microbiology central laboratory at Narayana nethralaya hospital,Bommasandra Bangalore. 94 samples were collected using a surgical scalpel blade no. 15 and it was subjected to microscopic Gram stain examination and 10%Pottasium hydroxide (KOH) mount and culture techniques. 16 samples on Sabouraud dextrose agar (SDA) started growing after 72 h and these were initially floccose, with a white hairy growth with greyish surface and yellow reverse. No growth was seen on blood agar and chocolate agar after 1 week of incubation. Lacto phenol cotton blue (LPCB) staining was performed after seven days of incubation by tease mount method and observed by binocular compound microscope with low power x10 and high power ×45, which shows septate hyphae, ovoid conidia with truncated bases suggestive of Scedosporium species. Results: 16 samples on Sabouraud dextrose agar (SDA) started growing after 72 h and these were initially floccose, with a white hairy growth with greyish surface and yellow reverse, suggestive of Scedosporium species.10 samples showed white, floccose, cottony myceleal growth on SDA and LPCB mount shows slightly curved micro and macro conidia accumulating around tips of phialides, suggestive of fusarium species. 10 samples revealed phaeoid, brown fungus with hairy growth on SDA and LPCB mount showed septate, slightly tapering curved conidia suggestive of Curvularia species. Conclusion: majority of Scedosporium growth was observed in our study(44%), compared to Fusarium(27%) and Curvularia(27%) species. In our retrospective study we found that males(35%) are more infected with fungal keratitis than females(8.3%), age group 50 to 60 years were affected more with Scedosporium keratitis infection.