Risk factors for chronic necrotizing aspergillosis include advanced age, alcoholism, diabetes, and mild immunosuppression. Invasive pulmonary aspergillosis is mainly seen in severely immunocompromised people, especially those with hematological malignancies (cancers of the blood), bone marrow transplant recipients, and people on long-term corticosteroid therapy, such as prednisone. Allogeneic bone marrow transplant recipients have the highest risk of getting invasive aspergillosis. Lung transplant recipients are also at high risk. Parasitic
Parasitic infections associated with cavitations include echinococcosis and paragonimiasis. Echinococcus is a tapeworm that most commonly infects dogs; people become infected by ingesting food or water that contains Echinococcus eggs. This results in cysts forming in the body, most commonly in the liver, but lung involvement is seen in 10-30% of cases. The cysts in the lung sometimes look like cavities on imaging. Paragonimus westermani, also called the lung fluke, is a flatworm which is transmitted by eating freshwater crabs or crayfish containing metacercaria (the infective form of the tapeworm). They mature into adult lung flukes in the lung, where cavitations may be seen in 15-59% of cases. Paragonimiasis is common in East Asia and Southeast Asia. Noninfectious causes
Lung cancer
The most common cause of a single lung cavity is lung cancer. Usually, the cavity forms because the cancer grows more rapidly then its blood supply, resulting in necrosis (cell death) in the central part of the cancer. 81% of lung cancers that develop cavities over-express epidermal growth factor receptor (EGFR), which could be related to rapid growth, central necrosis, and cavity formation.
Imaging in pulmonary gangrene shows multiple small cavities joining together to form a large cavity. Mycobacterial
Mycobacteria that can cause cavitations include Mycobacterium tuberculosis and nontuberculous mycobacteria, most commonly Mycobacterium avium complex. Primary tuberculosis is caused by the initial infection with Mycobacterium tuberculosis and rarely results in the formation of lung cavities. 90% of people with primary tuberculosis are able to contain the infection and enter a latent phase. Reactivation tuberculosis, which is caused by the reactivation of latent tuberculosis, results in lung cavities visible on X-ray 30 to 50% of the time. There are frequently multiple cavities, and they most commonly occur in the apical and posterior segments of the upper lobes or the superior segment of the lower lobes. Cavitary tuberculosis is associated with worse outcomes, a higher rate of treatment failure, more frequent relapse after treatment, and a higher risk of transmitting the disease to others. Even after successful treatment with anti-tuberculosis drugs, 20-50% of patients with cavitary tuberculosis have persistent cavities, which results in decreased lung function and increased risk of opportunistic infections by Aspergillus fumigatus and other fungal pathogens.Nontuberculous mycobacteria (NTM) are all mycobacterial species other than Mycobacteria tuberculosis (which causes tuberculosis) and Mycobacterium leprae (which causes leprosy). NTM are found everywhere in the environment but are most commonly found in soil and water. Lung disease is caused by inhaling or ingesting nontuberculous mycobacteria. Unlike tuberculosis, NTM infection is not transmitted from person to person.