From the Guidelines
The diagnostic criteria for Allergic Bronchopulmonary Aspergillosis (ABPA) should include a predisposing condition, such as asthma or cystic fibrosis, along with essential components like A. fumigatus-specific IgE ≥0.35 kUA·L−1 and serum total IgE ≥500 IU·mL−1, as well as any two other components, including positive IgG against A. fumigatus, blood eosinophil count ≥500 cells·μL−1, or thin-section chest computed tomography consistent with ABPA 1. The diagnosis of ABPA should be suspected in patients with predisposing conditions or a compatible clinico-radiological presentation, such as expectoration of mucus plugs, fleeting opacities on chest imaging, finger-in-glove opacities, and lung collapse. Key diagnostic criteria include:
- Predisposing conditions, such as asthma, cystic fibrosis, chronic obstructive lung disease, or bronchiectasis
- Essential components:
- A. fumigatus-specific IgE ≥0.35 kUA·L−1
- Serum total IgE ≥500 IU·mL−1
- Other components (any two):
- Positive IgG against A. fumigatus
- Blood eosinophil count ≥500 cells·μL−1
- Thin-section chest computed tomography consistent with ABPA Important considerations for the diagnosis of ABPA include the presence of high-attenuation mucus, which is pathognomonic of ABPA, and elevated IgE against rAsp f1, f2, and f4, which supports the diagnosis of ABPA 1.
From the Research
Diagnostic Criteria for ABPA
The diagnostic criteria for Allergic Bronchopulmonary Aspergillosis (ABPA) are based on a combination of clinical, radiological, and immunological findings. The key criteria include:
- Elevation of total and specific IgE against Aspergillus fumigatus 2
- Presence of suggestive CT abnormalities such as mucoid impaction and consolidations 2
- Central bronchiectasis (CB) with normal tapering bronchi, a feature considered pathognomonic of ABPA 3
- Recurrent wheezing, fleeting pulmonary infiltrates, and bronchiectasis 4
Evolution of Diagnostic Criteria
The diagnostic criteria for ABPA have evolved over time, with various proposals and revisions:
- Rosenberg criteria (1977) were the first diagnostic criteria for ABPA, but lacked further elaboration on the weighting of diagnostic items and thresholds 4
- International Society for Human and Animal Mycology (ISHAM) proposed more specific diagnostic criteria in 2013 4
- Asano et al. proposed the ABPM diagnostic criteria in 2021, which showed superior diagnostic sensitivity compared to Rosenberg and ISHAM criteria 4
- ISHAM revised the ABPA diagnostic criteria again in 2024 and proposed diagnostic criteria for ABPM 4
Importance of Early Diagnosis
Early diagnosis of ABPA is crucial to prevent late complications such as bronchiectasis and fibrotic lung remodelling 5. Symptoms of ABPA can be highly variable and non-specific, overlapping with those of the underlying primary disease, making it essential to consider ABPA in patients with severe asthma, mould allergic patients with high serum IgE levels, and patients with cystic fibrosis 5.