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Annual Congress of Malaysian Thoracic Society
Symposium 5B
Orphan Lung Diseases
Allergic Bronchopulmonary Aspergillosis (ABPA) – What’s new?
Mat Zuki Mat Jaeb
Malaysia
Allergic Bronchopulmonary Aspergillosis (ABPA) is a hypersensitivity reaction to Aspergillus antigens that
is associated with inflammatory destruction of airways, occurs almost exclusively in patients with asthma
or cystic fibrosis (CF) who have concomitant atopy. The incidence of ABPA in patients with asthma and CF
is approximately 2% and 1 to 15% respectively. Aspergillus specific, IgE-mediated type I hypersensitivity
reactions and specific IgG-mediated type III hypersensitivity reactions are believed to play a central role
in the pathogenesis of ABPA. The persistence of A. fumigatus in the lung leads to T lymphocyte activation,
cytokine, and immunoglobulin (Ig) release and inflammatory cell recruitment. Local inflammation results in
mucus production, airway hyperreactivity, and ultimately bronchiectasis.
The most significant pathological findings in ABPA include bronchocentric granulomas and mucoid impaction
involving the bronchi and bronchioles. Granulomatous inflammation with histiocytes and lymphocytes,
increased numbers of eosinophils, and exudative bronchiolitis may be seen. Fungal hyphae were also
commonly seen without evidence of tissue invasion.
There is no single test or universally recognized set of criteria to diagnose ABPA. Integration of clinical,
radiographic, and serologic features and clinical judgment is used to make the diagnosis of ABPA.
The diagnostic criteria articulated by Rosenberg, and later revised by Greenberger, are widely accepted
which include presence of asthma, immediate skin reactivity to Aspergillus, serum precipitins to A fumigatus,
increased serum IgE and IgG level to A fumigatus, elevated total serum IgE more than 1,000 ng/mL, current
or previous pulmonary infiltrates, central bronchiectasis and peripheral eosinophilia (1,000 cells/µL).
The patient usually presents with wheezing, expectoration of brown mucus plugs, pleuritic chest pain, and fever.
The chest radiograph findings may be normal in the early stages of the disease. Fleeting pulmonary infiltrates
that tend to be in the upper lobe and central in location are typical findings during acute exacerbation.
There may be loss of lung volume due to mucoid impaction of the airways which manifest as “gloved finger
appearance”. Central bronchiectasis and pulmonary fibrosis may develop later in advance stage. A positive
sputum culture for A fumigatus is not essential for the diagnosis of ABPA. Immediate skin reactivity to
A fumigatus antigens and elevated levels of serum IgG antibodies to Aspergillus are usually present.
There are five recognized stages of ABPA. Stage I defines new, active ABPA. Stage II is marked by clinical and
serological remission. Stage III is recurrent active ABPA. Patients with chronic, steroid-dependent asthma
secondary to ABPA are classified as stage IV and fibro-cavitary disease due to progressive inflammation and
airway dilation defines Stage V, which may lead to progressive respiratory failure and death. Early diagnosis
and treatment is thought to be associated with a lower risk of advanced disease in the future. Changes in
serum total IgE level or pulmonary function tests are useful for assessing remission or recurrence of ABPA.
The goal of therapy is to induce remission which is defined by improvement in clinical symptoms, decrease in
total serum IgE level, resolution of radiographic opacities, and improvement in lung function. by suppressing
the inflammation. Systemic and inhaled corticosteroids, antifungal agents, and omalizumab, a monoclonal
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