Galactomannan and Anti-Aspergillus Antibody Detection for the Diagnosis of Invasive Aspergillosis

Abstract

The detection of circulating fungal antigens, such as galactomannan, might help in early diagnosis of invasive aspergillosis. As with galactomannan detection in serum, treatment of patients with mold-active antifungal agents decreases the performance of galactomannan detection in bronchoalveolar lavage . In one study galactomannan could not be detected in patients with invasive aspergillosis after 3 days of therapy. In other patient groups, such as solid organ transplant recipients, the detection of anti-Aspergillus antibodies might be useful for the diagnosis and management of invasive aspergillosis. An alternative approach could be to combine the detection of antigen and antibody for the diagnosis of invasive aspergillosis. An autopsy-controlled, nonrandomized pilot study evaluated the feasibility of combining the detection of circulating galactomannan and high-resolution CT for the management of invasive aspergillosis. Interestingly, the costs per patient in the preemptive group and the empiric group were not significantly different, which suggests that the costs saved in withholding antifungal therapy are similar to the increased costs of diagnostic tests and procedures in the preemptive group. Based on this study there appears to be no benefit of either strategy, although further studies are required to confirm this finding. In the past decades more insight has been obtained with respect to the performance of the galactomannan enzyme immunoassay (EIA) in different clinical specimens and in expanding patient populations. New assays have become available that could be combined with galactomannan detection, and the detection of anti-Aspergillus antibodies might become more important in the management of high-risk patients.