PTX3 and bacterial pneumonia: When we compared the 58 negative cases to the 12 patients with proven bacterial pneumonia (total N =70), PTX3 diagnostic accuracy was confirmed by AUC-ROC analysis (AUCROC =0.827, 95% CI =0.668 to 0.987, P <0.0001); however, BAL fluid sTREM-1, plasma PTX3, sTREM-1, CRP and PCT levels were not predictive of bacterial pneumonia (see Figure E1 in Additional file 1).