Aspergillosis is an infection caused by a type of mold. 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 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:
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:
A growth of tangled fungus fibers (fungus ball) may develop in air spaces (cavities) in the lung as part of chronic pulmonary aspergillosis. This type of aspergillosis is called simple aspergilloma. Lung cavities may develop in people with pre-existing lung conditions, such as emphysema, tuberculosis or advanced sarcoidosis.
Aspergilloma is a benign condition that may not produce symptoms or may produce a mild cough only, but over time, the underlying condition can worsen and possibly cause:
Invasive pulmonary aspergillosis — the most severe form — occurs when the infection spreads rapidly from the lungs to your brain, heart, kidneys or skin. This occurs only in people whose immune system is weakened, commonly from chemotherapy. Untreated, this form of aspergilla disease is usually fatal.
Signs and symptoms depend on which organs are affected, but in general, invasive aspergillosis can cause:
Aspergillus can invade areas of the body other than your lungs, such as your sinuses. In your sinuses, it can cause a stuffy nose, drainage that's possibly bloody, inflammation, fever, facial pain and headache.
If you have asthma or cystic fibrosis, see your doctor whenever you notice a change in your symptoms. Although aspergillosis may not be the cause, it's important to have 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, and treatment is sometimes started before the infection is diagnosed.
Aspergillus mold is unavoidable. Outdoors, it's found in decaying leaves and compost and on plants, trees and grain crops. Inside, the spores — the reproductive parts of mold — thrive in air conditioning and heating ducts, insulation, and some food and spices.
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.
Diagnosing an infection caused by aspergillus mold can be difficult and depends on the type of aspergillus infection. Aspergillus is common in the environment and is sometimes found in the saliva and sputum of healthy people. What's more, it's hard to distinguish aspergillus from certain other molds under the microscope, and symptoms of the infection are similar to those of conditions such as tuberculosis.
Your doctor is likely to use one or more of the following tests:
Depending on the type of infection, aspergillosis can cause a variety of serious complications:
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 the most obvious sources of mold, such as construction sites, compost piles and stored grain. If you have a weakened immune system, your doctor may advise you to wear a face mask to avoid being exposed to airborne infectious agents.
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: