Evaluation of a quantitative serum Aspergillus fumigatus-specific IgM assay for diagnosis of chronic pulmonary aspergillosis

Clin Respir J. 2018 Nov;12(11):2566-2572. doi: 10.1111/crj.12957. Epub 2018 Oct 21.

Abstract

Background: The early diagnosis of chronic pulmonary aspergillosis (CPA) remains challenging. Currently, a new quantitative IgM antibody assay that enveloped purified galactomannan extracted from Aspergillus fumigatus as antigen was commercially available in China, but its diagnostic value remains to be established.

Methods: To evaluate the role of this commercial IgM assay for diagnosis of CPA, a multi-center prospective study was performed in 12 hospitals in Zhejiang Province, from January 1 to December 31, 2016. Adult inpatients without severe immunocompromised condition and those with persistent clinical symptoms/radiological findings ≥3 months or a consistent appearance in chest CT that was suggestive of CPA were included. The clinical data were compiled using a structured questionnaire.

Results: A total of 87 cases were enrolled, including 43 CPA. The sensitivity ranged from 16.3% to 46.5%, and the specificity from 77.3% to 95.5% when cutoffs were from 50 to 80 arbitrary unit (AU)/mL. The receiver operating characteristic analysis revealed an area under the curve of 0.627. When a cutoff of 38.12 AU/mL was applied, the sensitivity and specificity were 69.8% and 56.8%, respectively, which represents the best performance.

Conclusions: To our knowledge, this study was the first to evaluate this commercial A. fumigatus-specific IgM antibody assay in CPA patients in China and indicates that this IgM assay has a limited value and should not be a prior recommendation for CPA diagnosis.

Keywords: CPA; chronic pulmonary aspergillosis; diagnostic value; serum Aspergillus fumigatus-specific IgM antibody assay.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Aspergillus fumigatus / immunology*
  • Aspergillus fumigatus / isolation & purification
  • China / epidemiology
  • Chronic Disease
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Female
  • Humans
  • Immunoglobulin M / immunology
  • Inpatients / statistics & numerical data
  • Male
  • Middle Aged
  • Prospective Studies
  • Pulmonary Aspergillosis / blood*
  • Pulmonary Aspergillosis / diagnosis*
  • Pulmonary Aspergillosis / diagnostic imaging
  • Pulmonary Aspergillosis / microbiology
  • Tomography, X-Ray Computed

Substances

  • Immunoglobulin M