A (1–3)-β-D-glucan (BDG) test on a serum sample is an easily obtained, early screening test when there is a suspicion of IPA. Although performance might be superior to serum Aspergillus antigen testing for the detection of IPA in the ICU [33], BDG negativity cannot be used to rule out infection, with a 77% sensitivity determined across a heterogeneous population of invasive aspergillosis patients, and performance in CAPA as yet to be determined. BDG positivity can occur due to a number of reasons in this patient cohort, however serial positive tests increases specificity and should prompt a diagnostic work-up including computed tomography and bronchoscopy and testing for Aspergillus antigen as outlined above [34]. While initiating antifungal treatment pre-emptively based on BDG positivity may be an improvement on empirical therapy, every effort should be made to utilise other more specific diagnostic tests to complement the BDG result.