Aspergillosis

Aspergillosis is an infection caused by a type of mold (fungus). The illnesses resulting from aspergillosis infection usually affect the respiratory system, but their signs and severity vary greatly.

The mold that triggers the illnesses, aspergillus, is everywhere — indoors and outdoors. Most strains of this mold are harmless, but a few can cause serious illnesses when people with weakened immune systems, underlying lung disease or asthma inhale their fungal spores.

In some people, the spores trigger an allergic reaction. Other people develop mild to serious lung infections. The most serious form of aspergillosis — invasive aspergillosis — occurs when the infection spreads to blood vessels and beyond.

Depending on the type of aspergillosis, treatment may involve observation, antifungal medications or, in rare cases, surgery.

The signs and symptoms of aspergillosis vary with the type of illness you develop:

Allergic reaction

Some people with asthma or cystic fibrosis have an allergic reaction to aspergillus mold. Signs and symptoms of this condition, known as allergic bronchopulmonary aspergillosis, include:

• Fever
• A cough that may bring up blood or plugs of mucus
• Worsening asthma

Aspergilloma

Certain chronic lung (pulmonary) conditions, such as emphysema, tuberculosis or advanced sarcoidosis, can cause air spaces (cavities) to form in the lungs. When people with lung cavities are also infected with aspergillus, fungus fibers may find their way into the cavities and grow into tangled masses (fungus balls) known as aspergillomas.

Aspergillomas may produce no symptoms or cause only a mild cough at first. Over time and without treatment, however, aspergillomas can worsen the underlying chronic lung condition and possibly cause:

• A cough that often brings up blood (hemoptysis)
• Wheezing
• Shortness of breath
• Unintentional weight loss
• Fatigue

Invasive aspergillosis

This is the most severe form of aspergillosis. It occurs when the infection spreads rapidly from the lungs to the brain, heart, kidneys or skin. Invasive aspergillosis occurs only in people whose immune systems are weakened as a result of cancer chemotherapy, bone marrow transplantation or a disease of the immune system. Untreated, this form of aspergillosis may be fatal.

Signs and symptoms depend on which organs are affected, but in general, invasive aspergillosis can cause:

• Fever and chills
• A cough that brings up blood (hemoptysis)
• Shortness of breath
• Chest or joint pain
• Headaches or eye symptoms
• Skin lesions

Other types of aspergillosis

Aspergillus can invade areas of your body other than your lungs, such as your sinuses. In your sinuses, the fungus can cause a stuffy nose sometimes accompanied by drainage that may contain blood. Fever, facial pain and headache may also occur.

If you have asthma or cystic fibrosis, see your doctor whenever you notice a change in your breathing. Although aspergillosis may not be the cause, it's important to have breathing problems evaluated.

If you have a weakened immune system and develop an unexplained fever, shortness of breath or a cough that brings up blood, get immediate medical care. In the case of invasive aspergillosis, prompt treatment is crucial. In some cases, treatment with antifungal medication begins as soon as aspergillosis is suspected, even before testing has confirmed the diagnosis.

Aspergillus mold is unavoidable. Outdoors, it's found in decaying leaves and compost and on plants, trees and grain crops.

Everyday exposure to aspergillus is rarely a problem for people with healthy immune systems. When mold spores are inhaled, immune system cells surround and destroy them. But people who have a weakened immune system from illness or immunosuppressant medications have fewer infection-fighting cells. This allows aspergillus to take hold, invading the lungs and, in the most serious cases, other parts of the body.

Aspergillosis is not contagious from person to person.

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.

Depending on the type of infection, aspergillosis can cause a variety of serious complications:

• Bleeding. Both aspergillomas and invasive aspergillosis can cause severe, and sometimes fatal, bleeding in your lungs.
• Systemic infection. The most serious complication of invasive aspergillosis is the spread of the infection to other parts of your body, especially your brain, heart and kidneys. Invasive aspergillosis spreads rapidly and may be fatal.

It's nearly impossible to avoid exposure to aspergillus, but if you have had a transplant or are undergoing chemotherapy, try to stay away from places where you're likely to encounter mold, such as construction sites, compost piles and buildings that store grain. If you have a weakened immune system, your doctor may advise you to wear a face mask to avoid being exposed to aspergillus and other airborne infectious agents.