From the Guidelines
Allergic bronchopulmonary aspergillosis (ABPA) should be confirmed through a combination of clinical, radiological, and laboratory findings, and treated with oral prednisolone or itraconazole monotherapy for acute cases, with prednisolone and itraconazole combination only for treating recurrent ABPA exacerbations, as recommended by the revised ISHAM-ABPA working group clinical practice guidelines 1.
Diagnosis of ABPA
Diagnosis typically requires the presence of asthma or cystic fibrosis, immediate skin reactivity to Aspergillus antigens, elevated total IgE (usually >500 IU/mL), elevated specific IgE and IgG antibodies to Aspergillus fumigatus, and pulmonary infiltrates on imaging. The diagnostic criteria for ABPA include:
- Associated clinical deterioration (increased cough, wheeze, increased sputum production, worsening lung function, exacerbations)
- Total serum IgE level >500 IU/mL
- Immediate cutaneous reaction to Aspergillus (skin prick test weal of >3 mm in diameter with surrounding erythema, patient not on systemic antihistamines at the time) 1.
Treatment of ABPA
Treatment consists of two main approaches: oral corticosteroids and antifungal therapy.
- Oral prednisolone or itraconazole monotherapy is recommended for treating acute ABPA 1.
- Prednisolone and itraconazole combination is recommended only for treating recurrent ABPA exacerbations 1.
- Itraconazole may be used as an alternative to oral prednisolone, especially where systemic glucocorticoids are contraindicated 1.
- Patients should be monitored regularly with pulmonary function tests and IgE measurements to assess treatment response 1.
Key Considerations
- Asymptomatic ABPA patients do not routinely require systemic therapy, but treatment decisions should be individualized 1.
- Environmental control measures to reduce Aspergillus exposure are also important, including avoiding compost piles, construction sites, and ensuring proper home ventilation 1.
From the Research
ABPA Confirmation
- ABPA confirmation is based on a combination of clinical, radiologic, and immunologic criteria 2, 3, 4, 5, 6
- Essential criteria for ABPA diagnosis include asthma, positive skin prick test (SPT) for Aspergillus fumigatus, elevated serum total IgE, elevated serum AF-specific IgE, and pulmonary infiltrates seen on chest radiography or central bronchiectasis seen on CT scan 4
- Minimal essential criteria include asthma, SPT positivity, and central bronchiectasis 4
- High-resolution computed tomography (HRCT) of the chest is a useful radiologic tool for diagnosing ABPA, demonstrating central bronchiectasis, centrilobular nodules, and mucus impaction 5
ABPA Treatment
- Prednisone is the most definitive treatment for ABPA, with a usual course of 3 months 2, 3
- Itraconazole and voriconazole are adjunctive treatments, but drug-drug interactions must be considered 2
- Early diagnosis and treatment are crucial to prevent progression of the disease and alleviate clinical manifestations 5, 6
- Treatment can help prevent complications such as pulmonary fibrosis, bronchiectasis with chronic sputum production, and increasingly severe persistent asthma with loss of lung function 6
Diagnostic Challenges
- ABPA is often underdiagnosed and undertreated due to the lack of standardized diagnostic criteria and screening 6
- There is no single test that establishes the diagnosis of ABPA, and a combination of criteria is required for confirmation 6
- Central bronchiectasis with normal tapering bronchi is considered pathognomonic of ABPA, but other conditions can also cause similar radiologic findings 2, 6