From Culture to Fungal Biomarkers: the Diagnostic Route of Fungal Infections in Children with Primary Immunodeficiencies

Abstract

To provide an overview of the diagnostic tests available to identify invasive fungal disease (IFD) in children with a primary immunodeficiency and to evaluate the relative strengths and weaknesses of those tests. Novel tools to aid the diagnosis of IFD, such as fungal PCRs and lateral flow devices (for Aspergillus spp.), are emerging. However, the paucity of high-quality, multicentre clinical trials evaluating the performance of these diagnostic tools, particularly in the paediatric cohort of interest, remains a challenge. Children with primary immunodeficiencies are seldom referenced in existing studies. It is difficult to provide recommendations for the majority of fungal diagnostic tests, with the exception of histopathology, microscopy, culture, and imaging modalities, due to their poorly studied and largely unvalidated nature. Moving forward, multicentre trials considering the role of these tools in the investigation of children with probable IFD and a primary immunodeficiency are strongly encouraged.