Improving the rates of Aspergillus detection: an update on current diagnostic strategies

Introduction: The spectrum of disease caused by Aspergillus spp. is dependent on the immune system of the host, and ranges from invasive aspergillosis (IA) to chronic pulmonary aspergillosis (CPA). Early and reliable diagnosis of Aspergillus disease is important to decrease associated morbidity and mortality. Areas covered: The following review will give an update on current diagnostic strategies for the diagnosis of IA and CPA. Expert commentary: Several new diagnostics for IA (including point-of-care tests) are now available to complement galactomannan testing. In particular, immunoPET/MRI imaging may be a promising approach for diagnosing IA in the near future. Notably, nearly all new biomarkers and tests for IA have been evaluated in the hematology setting only. Validation of biomarkers and tests is therefore needed for the increasing proportion of patients who develop IA outside the hematology setting. As an important first step, reliable definitions of IA are needed for non-hematology settings as clinical presentation and radiologic findings differ in these settings. CPA diagnosis is based on a combination of radiological findings in chest CT, mycological evidence (e.g. by the Aspergillus-specific IgG assay), exclusion of alternative diagnosis and chronicity. ([18F]FDG) PET/CT and immuno PET/MRI imaging are promising new imaging approaches.