title: Detection of Aspergillus fumigatus hyphae in respiratory secretions by membrane filtration, fluorescent labelling and laser scanning.
abstract: The detection of Aspergillus fumigatus hyphae in bronchoalveolar lavage fluid (BAL) and sputum is diagnostically useful in patients at risk of invasive aspergillosis. We report a dedicated enzymatic-chemical sample pretreatment that allows the application of a previously described solid phase cytometry (SPC) method for detection of A. fumigatus hyphae in sputum and BAL samples. Non-specific detection of fungal hyphae by SPC is based on a 'viability' staining using carboxyfluorescein diacetate. For a specific detection of A. fumigatus hyphae by SPC, viability staining is combined with a pre-incubation at 45 degrees C, immunofluorescent labelling and microscopic recognition of the characteristic hyphal morphology. Low numbers of A. fumigatus hyphae (2-10 hyphae/sample) have now been demonstrated in spiked sputum using the non-specific and specific staining in 2.5 and 8.5 h, respectively.
authors.affiliation: Laboratory for Pharmaceutical Microbiology, Ghent University, Harelbekestraat 72, B-9000, Ghent, Belgium.
authors.forename: M M
authors.initials: MM
authors.lastname: De Vos
authors.forename: N N
authors.initials: NN
authors.lastname: Sanders
authors.forename: H J
authors.initials: HJ
authors.lastname: Nelis
mesh_terms: D001228:Aspergillosis / Q000175:diagnosis / Q000382:microbiology*; D001232:Aspergillus fumigatus / Q000302:isolation & purification*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D005374:Filtration / Q000379:methods; D005452:Fluoresceins / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D025301:Hyphae; D047569:Laser Scanning Cytometry / Q000379:methods; D013183:Sputum / Q000382:microbiology*
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; C027780:carboxyfluoresceindiacetate