In the study by Alanio et al. [9] which reported evidence of CAPA in nine (33%) out of 27 ventilated patients who underwent BAL/tracheal aspirate, one case was defined based on a BAL GM of 0.89 (below the usual cut-off of 1.0), two based on tracheal aspirate rather than BAL culture, one based on a serum GM of 0.51 (cut-off being 0.50) and in four cases BAL culture was positive but BAL GM negative, which suggests a lack of tissue invasion.