Allergic bronchopulmonary aspergillosis is commonly known as ABPA. It affects an estimated 4.8 million people worldwide. It occurs in an estimated 1-2% of patients with asthma, though reports are higher in some settings. Poorly controlled asthma is common in people with APBA. Only 19% of people with APBA have well-controlled asthma.
What is allergic bronchopulmonary aspergillosis?
ABPA is an allergic reaction or hypersensitivity to the fungus Aspergillus fumigatus (A. Fumigatus). It most commonly affects people living with asthma or cystic fibrosis. Many people with ABPA also suffer from other allergic conditions. They may also have atopic dermatitis (eczema), urticaria (hives), allergic rhinitis (hay fever) and sinusitis.
Aspergillus fumigatus is a type of mold (fungus) that is commonly found both indoors and outdoors. You may find it in soil, decaying vegetation, foods, dust and water. The fungal spores can be inhaled easily into the respiratory tract. The mold rarely makes people sick. For people with compromised immune systems, asthma or cystic fibrosis, it can cause problems.
People with asthma (and cystic fibrosis) often have increased mucus production. With ABPA, the mold does not invade the lungs. Rather the mucus becomes colonized with aspergillus in the respiratory tract. This may lead to recurrent inflammation of the lung. Left untreated, it can cause a condition called bronchiectasis. Bronchiectasis is when the airways become permanently widened. It may also lead to lung scarring.
ABPA is a type of allergic aspergillosis. It should not be confused with infectious aspergillosis diseases. This includes invasive aspergillosis, a serious infection that often impacts the lungs. This condition is most common in people with compromised immune systems.
What are the symptoms of allergic bronchopulmonary aspergillosis?
The symptoms of ABPA aspergillosis may not be obvious. People often first notice a worsening of their asthma symptoms. Some may also have a fever.
Allergic bronchopulmonary aspergillosis symptoms include:
- Asthma symptoms:
- Shortness of breath
- Chest pain or tightness
- Cough with bloody mucus or brownish flecks or plugs
- Fever that may go away and come back
- General fatigue, weakness or malaise
When do you suspect ABPA?
Your doctor may suspect ABPA if your asthma symptoms start worsening or you experience frequent asthma attacks. Worsening asthma symptoms or frequent or severe asthma attacks should always be of concern. Any patient experiencing these should make an appointment to see an asthma specialist.
What are the first symptoms of Aspergillus?
- Shortness of breath
How common is allergic bronchopulmonary aspergillosis?
ABPA is considered a rare disease. It affects approximately 4.8 million people worldwide. It occurs in an estimated 1-2% of people with asthma. However, asthma clinics report about 13% of patients having the condition. This could be because people with more persistent asthma symptoms are treated in asthma clinics frequently. Experts also believe the condition may be underdiagnosed.
How do you test for allergic bronchopulmonary aspergillosis?
If your doctor suspects you may have ABPA, there are several tests they may order. The diagnosis is made based on symptoms and results of those tests.
Tests may include:
- Blood tests to evaluate IgE levels and look for signs of an allergy
- A blood or skin test for specific IgE levels to aspergillus
- CT scan, which provided a detailed view of the lungs
- Sputum sample
Chest X-rays may be conducted but they are often not helpful in diagnosing ABPA, according to the American Thoracic Society.
Lung function testing (spirometry) may be used to see how severe your lung problem is and to find out how you are responding to the treatment.
How can ABPA complicate asthma?
People with asthma and ABPA may experience worsening asthma symptoms and control. Studies have also found how ABPA can damage the lungs and respiratory tract.
There are five stages of ABPA:
- corticosteroid-dependent asthma
Patients with end-stage ABPA may have extensive bronchiectasis resembling end- stage cystic fibrosis.
Delaying treatment for ABPA may result in pulmonary fibrosis, bronchiectasis, chronic mucus production, and severe persistent asthma, and loss of lung function. This is why it is really important for people with worsening asthma symptoms to see their asthma specialist. Early treatment of ABPA may help prevent disease progression.
How do you treat bronchopulmonary aspergillosis?
- Asthma symptom control
- Prevention of pulmonary exacerbations of ABPA
- Reducing or remitting pulmonary inflammation
- Reducing progression to end-stage disease
Oral glucocorticoids remain the primary treatment for ABPA, normally tapered over a course of three months. Antifungal therapy may also be included in treatment for patients. This is for patients unable to tolerate steroid tapers or for acute exacerbations. Inhaled corticosteroids may be used as an add-on treatment but should not be used as first-line therapy.
Treatment also includes ongoing monitoring of symptoms, lab tests and imaging. Your doctor may check your IgE antibody levels over the course of treatment. Elevated IgE levels may indicate an ongoing allergic response.
Allergic bronchopulmonary aspergillosis treatment includes:
- Oral glucocorticoids (such as prednisone or prednisolone)
- Antifungal agents (itraconazole and voriconazole)
- Biologic medication (omalizumab)
- Continuing asthma medications for symptom control
How long is treatment for aspergillosis?
The initial treatment for ABPA is a course of oral glucocorticoids for 14 days, then tapered over a course of 3 months. Relapses are possible, so patients with ABPA will require ongoing monitoring for recurrence.
Can allergic bronchopulmonary aspergillosis be cured?
ABPA aspergillosis cannot be cured, but it can go into remission. When the disease is in remission, it is considered in stage 2. Remission is considered when a person is:
- asthma is controlled
- has no new X-ray findings or rise in IgE levels for at least six months
Reviewed by Bradley Chipps, MD, FACAAI, a board-certified allergist and pediatric pulmonologist with Capital Allergy and Respiratory Disease Center in Sacramento, California. Dr. Chipps is Past President of the American College of Allergy, Asthma and Immunology (ACAAI).