Diagnostic Approaches for Aspergillus Infections


J Prattes, HJF Salzer, M Hoenigl
Published on 19 March 2019 Front. Microbiol.


About this Research Topic

Infections caused by Aspergillus spp. are associated with devastating mortality rates. Early and reliable diagnosis and subsequent rapid initiation of appropriate antifungal therapy has shown to improve survival significantly, at least for invasive Aspergillosis. However, invasive Aspergillus infections progress rapidly and are difficult to diagnose especially at early stages. Culture based approaches are important for detection of fungal species and resistance testing, however they are limited by low sensitivities – in particular during early phases of infection – and long turnaround time. Important advances to the field were brought by the introduction of non-cultural diagnostic tests for Aspergillosis in blood and bronchoalveolar lavage fluid, including, Galactomannan antigen testing, PCR, and Beta-D-Glucan testing in patients at risk. Complicating is the fact that performance of these tests may vary not only by fungal disease, but also by risk group (e.g. neutropenic patients versus non-neutropenic patients, neonates versus adults, antimould prophylaxis ver-sus no antimould prophylaxis). 

In addition, several new diagnostic approaches for IA diagnosis have been studied within the last years (for example the Aspergillus specific lateral flow assay, imaging studies using radiolabeled siderophores, analyses of volatile organic compounds in exhaled breath samples, new proxim-ity ligation assays and so on). These new diagnostic approaches may overcome the limitations observed with the currently available diagnostic tools, like e.g., decreased sensitivities under antifungal prophylax-es/treatment, low specificity, long turn-around times.
In contrast to the invasive form chronic pulmonary Aspergillosis (CPA) is usually seen in immunocompetent patients with underlying respiratory diseases. 

The vast majority with 1.2 out of 3 mil-lion CPA patients worldwide develop CPA as sequel to pulmonary tuberculosis. Hence, the highest burden of CPA might be covered by high TB incidence countries of low-resources. Disease severity and progression is highly variable with a five year fatality rate between 40-60%. Diagnosis is often challenging and made by a combination of characteristics. To prove mycological evidence Aspergillus IgG antibody assays are high-ly recommend with variable sensitivity and specificity depending on which assay is used. Management of CPA patients needs a long-term commitment with a multimodal and personalized approach.

This Research Topic will welcome the following manuscript types focusing on diagnosis of invasive and chronic forms of Aspergillosis: Original Research, Case Reports, Reviews, Mini-Reviews, Clinical Trial Protocols. We particularly welcome articles reporting novel diagnostic approaches, or involving novel patient groups for more established diagnostic tests.