Risk factors

Your risk of developing aspergillosis depends on your overall health and the extent of your exposure to mold. In general, these factors make you more vulnerable to infection:

• Weakened immune system. 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 at highest risk of invasive aspergillosis. People in the later stages of AIDS also may be at increased risk.
• Low white blood cell level. People who have had chemotherapy, an organ transplant or leukemia have lower white cell levels, making them more susceptible to invasive aspergillosis. So does having chronic granulomatous disease — an inherited disorder that affects immune system cells.
• Lung cavities. People who have air spaces (cavities) in their lungs are at higher risk of developing aspergillomas.
• Asthma or cystic fibrosis. People with asthma and cystic fibrosis, especially those whose lung problems are long-standing or hard to control, are more likely to have an allergic response to aspergillus mold.
• 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.