Alternative names
Acute invasive aspergillosis; Aspergillosis - acute invasive
Definition
The invasive type of pulmonary aspergillosis is an acute fungal infection of the lungs that produces illness almost exclusively in immunosuppressed or immunodeficient people.
Causes, incidence, and risk factors
Aspergillosis is caused by a fungus (aspergillus) that is commonly found in the environment. It grows on dead leaves, stored grain, bird droppings, compost piles, or other decaying vegetation.
It causes lung disease in three ways: as an allergic reaction in people with Asthma; as a fungus ball (aspergilloma) in an old healed lung cavity from previous disease such as Tuberculosis or lung abscess, and as an invasive infection with Pneumonia that may spread to other parts of the body through the bloodstream (invasive aspergillosis). Only the invasive infection is called invasive pulmonary aspergillosis and is much more serious than the other types of aspergillosis. The invasive infection can affect any organ of the body, but especially the heart, lungs, brain, and kidneys. Late in the course of the disease, the nervous system, skin, and other organs may become affected.
Risk factors in addition to immunosuppression include a very low white blood cell count over a prolonged period. This is especially a problem in patients with prolonged neutropenia (low white blood cell counts) following Chemotherapy or bone marrow transplantation.
Symptoms
Signs and tests
Listening to the chest with a stethoscope (auscultation) occasionally reveals crackles or a pleural friction rub - a sound made by the inflamed lining of the lung rubbing against the lung.
Tests may include:
Treatment
The objective of therapy is to reverse any correctable immunosuppression and to control the infection with antifungal medications. In the past, antifungal therapy was limited to amphotericin B. However, several less toxic agents have been found to have activity against aspergillus. These include itraconazole, voriconazole, and capsofungin.
Hospitalization will probably be necessary. To resolve any low white blood cell count that may be present, it is usually necessary to reduce or stop use of immunosuppressive drugs and begin treatment with granulocyte-colony-stimulating factor (GCSF).
Expectations (prognosis)
Patients with the invasive form of pulmonary aspergillosis are usually critically ill, and the disease is difficult to cure. Prognosis is often not good, and should be discussed with the health care provider in each case.
Complications
This infection can damage multiple organs, eventually causing multi-organ system failure.
Calling your health care provider
Call your health care provider if symptoms of this disorder develop. If you know you have a low neutrophil count (neutropenia) and have fevers or symptoms of a respiratory infection, you should notify your doctor immediately. An early diagnosis may improve the chance of a good outcome.
Prevention
People who are immunosuppressed because of disease or medications should avoid environments that are conducive to the growth of aspergillus fungus.