Characterization and comparison of galactomannan enzyme immunoassay and quantitative real-time PCR assay for detection of Aspergillus fumigatus in bronchoalveolar lavage fluid from experimental invasive pulmonary aspergillosis. Academic Article Article uri icon

Overview

MeSH

  • Animals
  • Antifungal Agents
  • Disease Models, Animal
  • Female
  • Mannans
  • Rabbits
  • Sensitivity and Specificity

MeSH Major

  • Aspergillosis
  • Aspergillus fumigatus
  • Bronchoalveolar Lavage Fluid
  • Immunoenzyme Techniques
  • Lung Diseases, Fungal
  • Polymerase Chain Reaction

abstract

  • Bronchoalveolar lavage (BAL) is widely used for evaluation of patients with suspected invasive pulmonary aspergillosis (IPA). However, the diagnostic yield of BAL for detection of IPA by culture and direct examination is limited. Earlier diagnosis may be facilitated by assays that can detect Aspergillus galactomannan antigen or DNA in BAL fluid. We therefore characterized and compared the diagnostic yields of a galactomannan enzyme immunoassay (GM EIA), quantitative real-time PCR (qPCR), and quantitative cultures in experiments using BAL fluid from neutropenic rabbits with experimentally induced IPA defined as microbiologically and histologically evident invasion. The qPCR assay targeted the rRNA gene complex of Aspergillus fumigatus. The GM EIA and qPCR assay were characterized by receiver operator curve analysis. With an optimal cutoff of 0.75, the GM EIA had a sensitivity and specificity of 100% in untreated controls. A decline in sensitivity (92%) was observed when antifungal therapy (AFT) was administered. The optimal cutoff for qPCR was a crossover of 36 cycles, with sensitivity and specificity of 80% and 100%, respectively. The sensitivity of qPCR also decreased with AFT to 50%. Quantitative culture of BAL had a sensitivity of 46% and a specificity of 100%. The sensitivity of quantitative culture decreased with AFT to 16%. The GM EIA and qPCR assay had greater sensitivity than culture in detection of A. fumigatus in BAL fluid in experimentally induced IPA (P+/-0.04). Use of the GM EIA and qPCR assay in conjunction with culture-based diagnostic methods applied to BAL fluid could facilitate accurate diagnosis and more-timely initiation of specific therapy.

publication date

  • July 2006

has subject area

  • Animals
  • Antifungal Agents
  • Aspergillosis
  • Aspergillus fumigatus
  • Bronchoalveolar Lavage Fluid
  • Disease Models, Animal
  • Female
  • Immunoenzyme Techniques
  • Lung Diseases, Fungal
  • Mannans
  • Polymerase Chain Reaction
  • Rabbits
  • Sensitivity and Specificity

Research

keywords

  • Comparative Study
  • Journal Article

Identity

Language

  • eng

PubMed Central ID

  • PMC1489482

Digital Object Identifier (DOI)

  • 10.1128/JCM.02693-05

PubMed ID

  • 16825367

Additional Document Info

start page

  • 2475

end page

  • 2480

volume

  • 44

number

  • 7