Galactomannan detection in bronchoalveolar lavage fluid

Prompt diagnosis of invasive pulmonary aspergillosis (IPA) remains a challenge. Galactomannan (GM) assay in serum has been incorporated into diagnostic criteria for IPA, but its performance varies depending on the population in which the test is used. GM assay on bronchoalveolar lavage (BAL) fluid aims to improve upon the test by applying it directly on samples from the target organ. The studies that have examined the utility of BAL-GM are a heterogeneous group, but the results are intriguing, especially in patients who are at risk for IPA from causes other than hematologic malignancy and neutropenia. BAL-GM had sensitivities ranging from 60% to 100% in this group, often far exceeding the performance of serum GM assay. The test shows promise as a useful adjunctive diagnostic modality in the diagnosis of IPA.