Skip to main content

Table 1 Analytical performance of the five methods utilized for P. aeruginosa detection from ETA samples compared to the extended gold standard

From: Evaluation of GeneXpert PA assay compared to genomic and (semi-)quantitative culture methods for direct detection of Pseudomonas aeruginosa in endotracheal aspirates

Methods Extended gold standarda Sensitivity (95% confidence interval) Specificity (95% confidence interval)
Positive (n = 41) Negative (n = 39)
Quantitative culture
 Positive 40 1 97.6% (87.1–99.9) 97.4% (86.5–99.9)
 Negative 1 38
Enrichment culture (4 samples could not be tested)
 Positive 34 0 89.5% (75.2–97.1) 100% (90.8–100)
 Negative 4 38
In-house qPCR (1 sample could not be tested)
 Positive 38 11 92.7% (80.1–98.5) 71.1% (54.1–84.6)
 Negative 3 27
GeneXpert PA assay
 Positive 40 0 97.6% (87.1–99.9) 100% (91.0–100)
 Negative 1 39
Semi-quantitative culture
 Positive 40 0 97.6% (87.1–99.9) 100% (91.0–100)
 Negative 1 39
  1. aP. aeruginosa detected by semi-quantitative culture plus one sample that showed P. aeruginosa presence by the other four methods but not by semi-quantitative culture