What is the recommended treatment approach for managing Allergic Bronchopulmonary Aspergillosis (ABPA)?

Treatment Approach for Allergic Bronchopulmonary Aspergillosis (ABPA)

The recommended first-line treatment for acute ABPA exacerbations is oral prednisolone (0.5 mg/kg/day for 2-4 weeks, tapered over 4 months) or oral itraconazole for 4 months, with the choice depending on the need for rapid symptom control versus minimizing side effects. 1, 2

Diagnosis and Classification

ABPA is classified radiologically into:

• ABPA-S (Serological): ABPA with no bronchiectasis
• ABPA-B: ABPA with bronchiectasis
• ABPA-MP: ABPA with mucus plugging
• ABPA-HAM: ABPA with high-attenuation mucus
• ABPA-CPF: ABPA with chronic pleuropulmonary fibrosis 1

Treatment Algorithm

1. Initial Treatment for Acute ABPA

Option A: Oral Prednisolone

• Dosage: 0.5 mg/kg/day for 2-4 weeks
• Taper: Over 4 months
• Best for: Patients needing rapid symptom control 1, 2

Option B: Oral Itraconazole

• Duration: 4 months
• Advantages: Better safety profile, fewer side effects
• Best for: Patients with contraindications to systemic glucocorticoids
• Monitoring: Target trough levels ≥0.5 mg/L 1, 2

2. Treatment for Recurrent or Treatment-Dependent ABPA

For patients with ≥2 exacerbations in 1-2 years:

• Combination therapy with oral prednisolone and oral itraconazole 2

Long-term maintenance options:

1. Long-term itraconazole
2. Nebulized amphotericin B (25 mg weekly)
3. Biological agents (omalizumab, mepolizumab, benralizumab, or dupilumab) 1

3. Management During Remission

• Treat underlying asthma and bronchiectasis per existing guidelines
• Monitor with clinical review, serum total IgE levels, and lung function tests every 3-6 months for the first year, then every 6-12 months
• Consider maintenance therapy with itraconazole, nebulized amphotericin B, or biological agents for treatment-dependent ABPA 1

Special Considerations

For Advanced ABPA with Extensive Bronchiectasis:

• Nebulized hypertonic saline (3-7%, 4-5 mL) preceded by nebulized salbutamol
• Nebulized antibiotics or long-term azithromycin for frequent infections
• Caution with azithromycin + itraconazole (QTc prolongation risk) 1

For Refractory Cases:

• Pulse doses of methylprednisolone for ABPA exacerbations refractory to oral glucocorticoids
• Alternative antifungals (voriconazole, posaconazole, isavuconazole) if itraconazole fails 2

Treatment Response Evaluation

Evaluate after 8-12 weeks using:

• Clinical symptoms (≥50% improvement indicates good response)
• Serum total IgE levels (≥20% reduction indicates good response)
• Chest imaging
• FEV1 (improvement of ≥158 mL indicates good response) 2

Important Cautions

1. High-dose inhaled corticosteroids alone should not be used as primary therapy for acute ABPA exacerbations 2, 3
2. Biological agents are not recommended as first-line therapy for acute ABPA 2
3. Combination of inhaled budesonide or fluticasone with itraconazole can cause exogenous Cushing's syndrome 2
4. Methylprednisolone with itraconazole increases risk of exogenous Cushing's syndrome and adrenal insufficiency 2
5. Correct vitamin D deficiency to prevent osteopenia with long-term glucocorticoid use 2

By following this structured approach to ABPA management, clinicians can effectively control symptoms, prevent exacerbations, minimize bronchiectasis progression, and reduce therapy-related adverse events.