ByPaschalis Vergidis, MD, MSc, Mayo Clinic College of Medicine & Science
Reviewed/Revised Nov 2023

Aspergillosis is an infection, usually of the lungs, caused by the fungus Aspergillus.

  • A ball of fungus fibers, blood clots, and white blood cells may form in the lungs or sinuses.

  • People may have no symptoms or may cough up blood or have a fever, chest pain, and difficulty breathing.

  • If fungi spread to the liver or kidneys, these organs may malfunction.

  • Diagnosis usually is based on the culture results of a sample of infected material and sometimes on an x-ray or computed tomography.

  • Antifungal medications are used, and sometimes surgery is needed to remove the fungal balls.

(See also Overview of Fungal Infections.)

Aspergilli are very common in the environment—indoors and out—and frequently occur in compost heaps, air vents, and airborne dust. These fungi are thus unavoidable.

Usually, aspergillosis is caused by inhaling Aspergillus spores. Most people inhale these spores every day without being affected. But if the immune system is weak, infection is more likely because aspergillosis is an opportunistic fungal infection (one that takes advantage of a weakened immune system). The immune system may be weakened by the following:

  • Disorders that affect the immune system (including AIDS and some hereditary disorders)

  • Cancer

  • Medications such as corticosteroids (if high doses are taken for a long time), cancer chemotherapy, or medications used to prevent an organ transplant from being rejected

Aspergillosis has several forms:

  • Pulmonary aspergillosis: Aspergillosis usually develops in open spaces in the body, such as cavities in the lungs caused by preexisting lung disorders. In the lungs, aspergillosis typically develops as a ball (aspergilloma) composed of a tangled mass of fungus fibers, blood clots, and white blood cells. The fungus ball gradually enlarges, destroying lung tissue in the process, but usually does not spread to other areas.

  • Sinus aspergillosis: The infection may also develop in the sinuses. In the sinuses, aspergillosis typically develops as an aspergilloma.

  • Invasive aspergillosis: Less often, aspergillosis becomes very aggressive and rapidly spreads throughout the lungs and often through the bloodstream to the brain, heart, liver, and kidneys. This rapid spread occurs mainly in people with a very weakened immune system.

  • Allergic bronchopulmonary aspergillosis: Some people who have asthma or cystic fibrosis develop a chronic allergic reaction with cough, wheezing, and fever if Aspergillus colonizes the lining of their airways.

  • Superficial aspergillosis: This form is uncommon. It may develop in burns, under bandages, after damage to the eye, or in the sinuses, mouth, nose, or ear canal.

Symptoms of Aspergillosis

Pulmonary aspergillosis

A fungus ball in the lungs may cause no symptoms and may be discovered only when a chest x-ray is taken for other reasons. Or it may cause repeated coughing up of blood and, rarely, severe, even fatal bleeding.

Sinus aspergillosis

Aspergillosis of the sinuses causes a feeling of congestion and sometimes pain, discharge, or bleeding from the nose. People may have fever, headache, and a runny nose. Sores may develop over the nose or sinuses, or on the gums or palate. People may also develop a blood clot (thrombosis) in the cavernous sinus (a large vein at the base of the skull).

Invasive aspergillosis

This form is a rapidly invasive infection in the lungs and often causes cough, fever, chest pain, and difficulty breathing. Without treatment, invasive aspergillosis is fatal.

Aspergillosis that spreads to other organs makes people very ill. Symptoms include fever, chills, shock, delirium, and blood clots. Kidney failure, liver failure (causing jaundice), and breathing difficulties may develop. This type of infection can be rapidly fatal.

Diagnosis of Aspergillosis

  • Culture, examination, and analysis of a sample of infected material

Doctors suspect aspergillosis based on symptoms.

To identify the fungus, doctors usually need to send a sample of infected material to a laboratory to grow (culture), examine, and analyze. A viewing tube (bronchoscope or rhinoscope) may be used to obtain this material from the lungs or sinuses. Sometimes a biopsy is necessary to obtain a sample.

An x-ray of the chest or a computed tomography (CT) scan of the chest or sinuses also provides clues for making the diagnosis.

Treatment of Aspergillosis

  • Antifungal medications

  • Sometimes surgery to remove fungi

Aspergillosis that affects only a sinus or a single area in the lung requires treatment but does not pose an immediate danger because it progresses slowly. However, if the infection is widespread or if people appear seriously ill or have a weakened immune system, treatment is started immediately.

Invasive aspergillosis

Any condition that is weakening the immune system should be corrected if possible. For example, doctors may advise people who are taking corticosteroids, which suppress the immune system, to stop.

Fungus balls in the lungs or sinuses (aspergillomas) usually do not require treatment with medications and do not usually respond to medications. If these balls cause bleeding (causing people to cough up blood) or other symptoms, they may need to be removed surgically. Surgery cures the infection but is often risky because many people with aspergillomas have other disorders.

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