Pulmonary actinomycosis is a rare and serious infection caused by a group of bacteria called Actinomyces. These bacteria are part of the normal flora of the mouth, throat, and gastrointestinal tract in humans and animals, and they can also be found in soil and water. When these bacteria enter the lungs through inhalation, they can cause an infection that can lead to a variety of respiratory symptoms.
The exact cause of pulmonary actinomycosis is not known, but it is believed to be related to the presence of the bacteria in the environment. Inhalation of dust or particles containing the bacteria is thought to be the primary mode of transmission. Other potential sources of infection include aspiration of saliva or other material containing the bacteria, surgical procedures, and even ingestion of contaminated food or water. The bacteria can also spread from one person to another through close contact.
Those at greatest risk of developing pulmonary actinomycosis are people with weakened immune systems due to diseases such as HIV/AIDS, diabetes, cancer, or those receiving immunosuppressive medications. Other risk factors include smoking, poor oral hygiene, and dental procedures, such as tooth extractions or root canals.
Pulmonary actinomycosis can be difficult to diagnose due to its similarity to other more common respiratory conditions, such as tuberculosis or pneumonia. It is usually diagnosed through a combination of physical examination, imaging tests, and laboratory analysis of a sputum sample. Treatment is normally a combination of antibiotics, surgery, and supportive care.