Diagnostic performance of the (1-3)-β-D-glucan assay in patients with Pneumocystis jirovecii compared with those with candidiasis, aspergillosis, mucormycosis, and tuberculosis, and healthy volunteers

PLoS One. 2017 Nov 30;12(11):e0188860. doi: 10.1371/journal.pone.0188860. eCollection 2017.

Abstract

Background: Diagnosis of pneumocystis pneumonia (PCP) relies on microscopic visualization of P. jirovecii, or detection of Pneumocystis DNA in respiratory specimens, which involves invasive procedures such as bronchoalveolar lavage. The (1-3)-β-D-glucan (BG) assay has been proposed as a less invasive and less expensive diagnostic test to rule out PCP. We therefore compared blood levels of BG in patients with PCP with those of patients with candidemia, chronic disseminated candidiasis (CDC), invasive aspergillosis, mucormycosis, and tuberculosis and those of healthy volunteers.

Methods: Adult patients who were diagnosed with PCP, candidemia, CDC, invasive aspergillosis, mucormycosis, and tuberculosis whose blood samples were available, and healthy volunteers were enrolled in a tertiary hospital in Seoul, South Korea, during a 21-month period. The blood samples were assayed with the Goldstream Fungus (1-3)-β-D-glucan test (Gold Mountain River Tech Development, Beijing, China).

Results: A total of 136 individuals including 50 patients P. jirovecii,15 candidemia, 6 CDC, 15 invasive aspergillosis, 10 mucormycosis, and 40 controls (20 TB and 20 healthy volunteers) were included. The mean±SD of the concentration of 1-3-β-D-glucan in the patients with PCP (290.08 pg/mL±199.98) were similar to those of patients with candidemia (314.14 pg/mL±205.60, p = 0.90 at an α = 0.005) and CDC (129.74 pg/mL±182.79, p = 0.03 at an α = 0.005), but higher than those of patients with invasive aspergillosis (131.62 pg/mL±161.67, p = 0.002 at an α = 0.005), mucormycosis (95.08 pg/mL±146.80, p<0.001 at an α = 0.005), and tuberculosis (103.31 pg/mL±140.81, p<0.001 at an α = 0.005) as well as healthy volunteers (101.18 pg/mL±197.52, p<0.001 at an α = 0.005). At a cut-off value > 31.25 pg/mL, which is highly sensitive for PCP versus tuberculosis plus healthy volunteers at the expense of specificity, the BG assay had a sensitivity of 92% (95% CI 81%-98%) and a specificity of 55% (95% CI 39%-71%).

Conclusions: The BG assay appears to be a useful adjunct test for PCP.

MeSH terms

  • Adult
  • Aged
  • Aspergillosis / diagnosis*
  • Candidiasis / diagnosis*
  • Case-Control Studies
  • Diagnosis, Differential
  • Female
  • Healthy Volunteers
  • Humans
  • Male
  • Middle Aged
  • Mucormycosis / diagnosis*
  • Pneumocystis carinii / isolation & purification*
  • Pneumonia, Pneumocystis / diagnosis*
  • Pneumonia, Pneumocystis / microbiology
  • Republic of Korea
  • Tuberculosis, Pulmonary / diagnosis*
  • beta-Glucans / analysis*

Substances

  • beta-Glucans
  • beta-1,3-glucan

Grants and funding

This study was supported by grants from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant no. HI16C0272), and the Asan Institute for Life Sciences (2015-0193) to Sung-Han Kim. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.