Risk factorsBy Mayo Clinic staff
Your risk of developing aspergillosis depends on your overall health and the extent of your exposure to mold, but in general, these factors make you more vulnerable to infection:
- Weakened immune system. This is the greatest risk factor for invasive aspergillosis. People taking immune-suppressing drugs after undergoing transplant surgery — especially bone marrow or stem cell transplants — or people who have certain cancers of the blood are the most severely affected. People with later stage AIDS also may be at increased risk.
- Low white blood cell level. White blood cells called neutrophils play a key role in fighting fungal infections. Having a very low level of these cells (neutropenia) due to chemotherapy, an organ transplant or leukemia makes you much more susceptible to invasive aspergillosis. So does having chronic granulomatous disease — an inherited disorder that affects immune system cells.
- Lung cavities. A mass of tangled fungus fibers (aspergilloma) can develop when mold spores germinate in a healed air space (cavity) in your lungs. Cavities are areas that have been damaged by radiation to the lung or by serious lung diseases such as tuberculosis or sarcoidosis — a noncancerous illness that causes inflammation in your lungs and other organs.
- Asthma or cystic fibrosis. People with asthma and cystic fibrosis are more likely to have an allergic response to aspergillus mold. This may be more likely to occur in people whose lung problems are long-standing or hard to control.
- Ankylosing spondylitis. This is an uncommon rheumatologic lung disease that affects primarily the spine. People with this disorder are more likely to develop aspergillomas, particularly if they're male smokers.
- Long-term corticosteroid therapy. Long-term use of corticosteroids may increase the risk of opportunistic infections, depending on the underlying disease being treated and what other drugs are being used.
- A hospital stay. Aspergillus mold is found on many hospital surfaces — bedrails, plants, surgical instruments, air conditioning ducts and insulation. Though healthy people aren't likely to be affected, people with a weakened immune system or serious illness are highly susceptible to infection.
- Genetic makeup. Genetic factors may make certain people more prone to aspergillosis infection.
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