P276 Molecular epidemiology of clinical filamentous fungi in Qatar beyond Aspergillus and Fusarium

Abstract

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM ObjectivesDue to an increasing number of patients at risk, (ie, with a highly compromised immune system and/or receiving aggressive chemotherapy treatment), invasive fungal infections (IFI) are increasingly being reported. They are associated with significantly high mortality rates. Aspergillus spp., particularly A. fumigatus, is the major cause of mold-related IFI around the world followed by Fusarium spp., however, other molds are emerging as human pathogens. The aim of this study was to explore the epidemiology and prevalence of the non-Aspergillus and non-Fusarium molds in human clinical samples over 11 years period in Qatar based tertiary hospital using molecular techniques.MethodsA total of 91 clinical specimens positive for molds belonging to 90 patients were recorded in about 11 years (September 2003 to November 2014). The isolates were identified based on morphological characteristics and by sequencing the internal transcribed spacer (ITS) gene. To confirm the identifications, a phylogenetic tree based on ITS sequences was constructed.ResultsMost patients were males (72%), 6% were immunocompromised, 12% had IFI, and 7% died within 30 days of diagnosis. The fungal isolates were recovered from a variety of clinical samples, including nails, skin, hair, scalp, nasal cavity, wounds, respiratory samples, body fluids, eye, ear, tissue, abscess, and blood specimens. Dematiaceous fungi were overall the most isolated (33/91, 36%), followed by dermatophytes (25/91, 27%), Mucorales (16/91, 18%), and other hyaline molds (17/91, 19%) (Fig. 1). Curvularia was the most isolated genus (22/91, 24%) and Mucorales were the major cause of IF (5/11, 45.5%) (Table 1). Superficial mycoses were caused by dermatophytes (66%) and non-dermatophytes (34%). Furthermore, rare fungi that are not commonly known to cause human disease were recovered such as Rhytidhysteron rufulum, Subramaniula asteroids, Dothichiza pimprina, and Quambalaria cyanescens.ConclusionThe current study highlights the epidemiology and spectrum of mold genera, other than Aspergillus and Fusarium, recovered from human clinical samples in Qatar, which can aid in surveillance of uncommon and emerging mycoses other than aspergillosis and fusuriosis.