My mother-in-law recently had a chest X-ray and was told she has a granuloma in her lung. What does that mean?
Answer From James M. Steckelberg, M.D.
A granuloma is a small area of inflammation. Granulomas are often found incidentally on an X-ray or other imaging test done for a different reason. Typically, granulomas are noncancerous (benign).
Granulomas frequently occur in the lungs, but can occur in other parts of the body and head as well. Granulomas seem to be a defensive mechanism that triggers the body to "wall off" foreign invaders such as bacteria or fungi to keep them from spreading. Common causes include an inflammatory condition called sarcoidosis and infections such as histoplasmosis or tuberculosis.
Granulomas in people without symptoms almost never require treatment or even follow-up imaging tests.
Sept. 26, 2018
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- Ohshimo S, et al. Differential diagnosis of granulomatous lung disease: Clues and pitfalls. European Respiratory Review. http://err.ersjournals.com/content/26/145/170012. Accessed Sept. 7. 2018.
- Nwawka OK, et al. Granulomatous disease in the head and neck: Developing a differential diagnosis. RadioGraphics. 2014;34:1240.
- Mukhopadhyay S, et al. Causes of pulmonary granulomas: A retrospective study of 500 cases from seven countries. Journal of Clinical Pathology. 2012;65:51.
- AskMayoExpert. Pulmonary nodules. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2017.
- Orm IM, et al. The formation of the granuloma in tuberculosis infection. Seminars in Immunology. 2014;26:601.
- Mukhopadhyay S, et al. Pulmonary necrotizing granulomas of unknown cause. Chest. 2013;144:813.
- Information for healthcare professionals about histoplasmosis. Centers for Disease Control and Prevention. https://www.cdc.gov/fungal/diseases/histoplasmosis/health-professionals.html. Accessed Sept. 7, 2018.