Which diagnostic tests are most effective for confirming a diagnosis of aspergillosis in patients with respiratory symptoms?

For confirming a diagnosis of aspergillosis in patients presenting with respiratory symptoms, the most effective diagnostic approach combines clinical assessment with targeted laboratory and imaging tests. Serum and bronchoalveolar lavage (BAL) galactomannan antigen testing is a cornerstone, offering high sensitivity and specificity for invasive aspergillosis, especially in immunocompromised patients NICE NG33 Ullmann et al. 2018. Fungal culture and microscopy of respiratory samples, including sputum and BAL fluid, support diagnosis but have lower sensitivity and longer turnaround times NICE NG33 Azoulay et al. 2020. Polymerase chain reaction (PCR)-based assays on respiratory specimens enhance detection rates and can complement galactomannan testing, although standardisation is variable NICE NG33 Azim & Ahmed 2024. High-resolution computed tomography (HRCT) of the chest is essential to identify characteristic radiological features such as nodules with halo signs or cavitations, which guide further diagnostic workup NICE NG33 Ullmann et al. 2018. Combining these modalities improves diagnostic accuracy, particularly in complex cases or non-neutropenic patients where clinical presentation may be atypical Azim & Ahmed 2024. Thus, an integrated diagnostic strategy using galactomannan antigen detection in serum and BAL, supported by PCR and imaging, is most effective for confirming aspergillosis in respiratory presentations NICE NG33 Ullmann et al. 2018Azoulay et al. 2020Azim & Ahmed 2024.