Table 1

Clinical performance of galactomannan EIA when testing plasma and serum samplesa

ParameterPerformance comparison for each pair of sample types with:
Plasma testingSerum testingb
Proven/probable IA vs no IFDPossible IA vs no IFDProven/probable IA vs no IFDPossible IA vs no IFD
Sensitivity (%; 95% CI)6/7 (85.7; 48.7–97.4)4/10 (40; 16.8–68.7)6/7 (85.7; 48.7–97.4)0/10 (0; 0–27.8)
Specificity (%; 95% CI)41/48 (85.4; 72.8–92.8)41/48 (85.4; 72.8–92.8)38/48 (79.2; 65.7–88.3)38/48 (79.2; 65.7–88.3)
PPV (%; 95% CI)6/13 (46.2; 23.2–70.9)10/17 (36.4; 15.2–64.6)6/16 (37.5; 18.5–61.4)0/10 (0; 0–27.8)
NPV (%; 95% CI)41/42 (97.6; 87.7–99.6)41/47 (87.2; 74.8–94.0)38/39 (97.4; 86.8–99.6)38/48 (79.2; 65.7–88.3)
LR+5.882.744.111.26
LR−0.170.700.18
DOR35.143.9122.8
  • a Proven/probable cases (n = 1/6), possible cases (n = 10), and no-invasive fungal disease (IFD) controls (n = 48) were defined using the revised EORTC/MSG criteria with serum GM EIA or Aspergillus respiratory culture used as the microbiological criterion. The one case of proven IA was negative by GM EIA in serum and plasma. It was diagnosed as a proven case of IFD, with lung tissue showing septate hyphae with a 45° branching angle, and A. fumigatus was cultured from a respiratory sample. Of the 6 probable cases, 4 were serum GM EIA positive only and 2 were serum GM EIA positive and respiratory culture positive. Possible cases had radiological evidence specific to IA but were lacking microbiological evidence. PPV, positive predictive value; NPV, negative predictive value; LR+, likelihood ratio positive; LR−, likelihood ratio negative; DOR, diagnostic odds ratio.

  • b As serum is a disease-defining criterion, an incorporation bias is introduced in favor of serum testing and is evident when analyzing data involving probable cases.