Potential Pathogens among Fungi Identified as Nonsporulating Molds from Blood Cultures

Abstract

Twenty-eight molds were isolated from clinical blood cultures and were unidentifiable by cellular morphology using conventional microscopy. Using the utility of amplification and direct sequencing of internal transcribed spacer region of ribosomal RNA gene, 93% of these fungi were identified. Seventy-one percents of the molds were found to be associated with plants or soil with no or few published cases of human disease. These include species of basidiomycetes and ascomycetes such as Botryosphaeria dothidea, Phomopsis flavodonflavus, Inonotus pachyphloeus, Earlilella scabrosa, Calocybe indica, Athelia pellicularis, Tinctoporellus epimiltinus, Trametes lactinea, Coprinellus aureogranulat and Xylaria feejeensis. Some of the nonsporulating molds were identified as pathogen or potential pathogens in immunocompetent or immunocompromised hosts. These include Schizophylum commune and hyphomycetes such as Cladosporium cladosporoides, Aspergillus niger and Fusarium equiseti. Basidiomycetes and hyphomycetes identified in the current study are ubiquitous in the environment and are almost similar to the species of molds reported from cutaneous and respiratory samples suggesting that the fungi may represent contaminants rather than true fangaemia. Results of this study emphasize the need of an effort to minimise blood culture contamination and support the recommendation to incorporate clinical, radiologic findings and positive blood culture for molds in the diagnosis and management of invasive mycosis.