title: Fluorescent in situ hybridization of pre-incubated blood culture material for the rapid diagnosis of histoplasmosis.
abstract: Fluorescence in situ hybridization (FISH) has been shown to be useful for the detection of Candida and Cryptococcus species in blood culture materials. FISH procedures for the detection of Histoplasma capsulatum var. capsulatum have not been reported so far. This study describes the development and evaluation of fluorescently labeled rRNA-targeting FISH probes to detect and identify H. capsulatum in blood cultures. All three analyzed H. capsulatum reference strains and clinical isolates showed positive signals with the newly designed specific oligonucleotide probes for H. capsulatum, whereas negative reactions were observed for all three nontarget yeast species and the two nontarget bacteria. The assay was also successfully applied for detections of H. capsulatum cells in pre-incubated blood culture samples of patients with clinical suspicion of histoplasmosis (n = 33). The described FISH-based assay was shown to be easy to apply, sensitive, and specific (compared to polymerase chain reaction) for the detection and identification of H. capsulatum in this proof-of-principle analysis. Larger multicentric assessments are recommended for a thorough diagnostic evaluation of the procedure.
authors.affiliation: Universidade do Estado do Amazonas, Manaus, Brazil.
authors.forename: Roberto Moreira
authors.initials: RM
authors.lastname: da Silva
authors.affiliation: Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil.
authors.forename: João Ricardo
authors.initials: JR
authors.lastname: da Silva Neto
authors.affiliation: Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil.
authors.forename: Carla Silvana
authors.initials: CS
authors.lastname: Santos
authors.affiliation: Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil.
authors.forename: Kátia Santana
authors.initials: KS
authors.lastname: Cruz
authors.affiliation: Department of Tropical Medicine at the Bernhard Nocht Institute, German Armed Forces Hospital of Hamburg, Hamburg, Germany.
authors.forename: Hagen
authors.initials: H
authors.lastname: Frickmann
authors.affiliation: Institute of Medical Microbiology, Justus-Liebig-University Giessen, Giessen, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Poppert
authors.affiliation: Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: Koshikene
authors.affiliation: Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil joao.souza@inpa.gov.br.
authors.forename: João Vicente Braga
authors.initials: JV
authors.lastname: de Souza
mesh_terms: D001769:Blood / Q000382:microbiology*; D006658:Histoplasma / Q000235:genetics / Q000302:isolation & purification*; D006660:Histoplasmosis / Q000175:diagnosis* / Q000382:microbiology; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D015345:Oligonucleotide Probes / Q000235:genetics; D012331:RNA, Fungal / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D015345:Oligonucleotide Probes; D012331:RNA, Fungal; D012335:RNA, Ribosomal
keywords: FISH; development; histoplasmosis; molecular probes