Pulmonary aspergillosis - allergic bronchopulmonary type

Alternative names

Aspergillosis - allergic bronchopulmonary; Allergic bronchopulmonary aspergillosis; ABPA

Definition

Pulmonary aspergillosis is an allergic reaction to a fungus called aspergillus, which causes inflammation of the airways and air sacs of the lungs.

Causes, incidence, and risk factors

The aspergillus fungus is common. It can grow on dead leaves, stored grain, bird droppings, compost stacks and other decaying vegetation. Although most people are frequently exposed to aspergillus, infections caused by it such as a pneumonia or fungus ball (aspergilloma) are rare.

Some people, however, have an allergic reaction (hypersensitivity) to this fungus, which is called allergic bronchopulmonary aspergillosis (ABPA). It is characterized by inflammation of the airways (bronchi) or air sacs (alveoli). The disease may mimic asthma or Pneumonia, and, in fact, most patients with ABPA have asthma as well.

Patients with Asthma or Cystic fibrosis are at highest risk for allergic aspergillosis.

Symptoms

• worsening symptoms of Asthma
  
• wheezing
  
• cough may produce brownish plugs or bloody sputum
  
• fever
  

Signs and tests

• elevated CBC eosinophil count
  
• elevated serum IgE antibodies: total IgE level and level of IgE specific for aspergillus
  
• aspergillus antigen skin test
  
• positive serum aspergillus antibodies
  
• Chest x-ray showing infiltrates and finger-like shadows
  
• chest CAT scan showing central bronchiectasis (dilation of the airways) or mucous plugging
  
• sputum stain and culture for fungus
  
• bronchoscopy with cultures and transbronchial biopsy
  
• rarely lung biopsy is required
  

Treatment

Allergic aspergillosis is treated with oral prednisone. The anti-fungal antibiotic, itraconazole, can also be helpful. People with should also continue their usual inhaler treatments.