Nearly 5% of asthmatics may develop ABPA at some point. A study of Cystic Fibrosis patients in Australia between 1998 and 2002 reports that nearly 19% had been colonized (i.e. infected) with Aspergillus. However, determining the prevalence of apergiullus colonization in patients with CF is difficult.
ABPA stands for "allergic broncho pulmonary aspergilliosis." It means that in addition to culturing aspergillus (a type of fungus), the body reacts to it with an allergic response. Some people can culture aspergillus but don't have ABPA. The body responds to the allergen by increasing the amount of IgE (immunoglobulin E) in the blood. To bring the IgE back down and control the fungal infection, doctors prescribe antifungal medications like Vfend or Sporanox in combination with corticosteroids (such as prednisone) to reduce inflammation in the lungs and/or sinuses.
A IgE number of 100 or greater is considered "high" for adults. During periods of acute exacerbation, it can climb into the thousands. When this happens,the first thing the doctors would try is prednisone. For some however, prednisone is worse than the infection itself since it brings about so many horrible side effects.
High IgE levels are presumed to be associated with a decrease in lung function. The significance and danger of a high IgE number is that if IgE numbers stay high for a prolonged period of time, the degree of severity of lung damage can potentially increase. However, this is largely just a hypothesis on my part based on things I've read. IgE and its connection with lung function is something that isn't fully understood at this point in time but several studies are ongoing.
A doctor will determine the best course of treatment based on the prevailing symptoms (cough, hemoptysis, fatigue, weight loss) as well as lab culture results. An aspergillus specific IgE blood test can be performed. Which medications are used depends on whether the infection is invasive or non-invasive, and where the infection lies. In patients with cystic fibrosis, an aspergillus infection may start in the upper respiratory tract (e.g. sinuses) and spread to the lower respiratory tract. More aggressive treatments and higher dosages of drugs or combinations of drugs are required to treat invasive aspergilliosis. Avoiding an aspergillus infection in the first place involves making sure that the home environment is free from the conditions that would encourage mold growth (i.e. moisture, dampness, live plants, etc.) Once aspergillus takes hold in the body, completely eradicating it is difficult. Antifungal therapies may be required for long periods of time, especially in people who are already prone to upper respiratory infection.