Among the 23 patients without pneumonia and with PTX3 levels ≥1 ng/ml in BAL fluid, 5 had cardiogenic pulmonary edema, 9 had ARDS of extrapulmonary origin, 4 had primary noninfectious ARDS and 2 had acute exacerbations of chronic obstructive pulmonary disease (all representing acute inflammatory conditions of lung that can elevate unspecific biomarkers like PTX3), and a final diagnosis could not be determined in 3 patients. Here, PTX3 is linked to susceptibility to pneumonia measurement.