What Is a Lung Nodule?
A lung nodule, also referred to as a pulmonary nodule, is a mass of tissue located in the lungs. Most lung nodules are benign or non-cancerous, but large masses can be signs of cancer. Symptoms of lung nodules are subtle and may include a tight feeling in the chest, making it easily confused with the flu or a chest cold. Non-cancerous lung nodules can be caused by a variety of conditions that affect the lungs. Tuberculosis, an infection caused by Mycobacterium tuberculosis bacteria, often spreads to the lungs and forms lung nodules. Histoplasmosis, an infection caused by inhalation of the Histoplasma capsulatum fungus found in certain bat and bird droppings, may attack the lungs and cause nodules. Benign lung nodules can also be caused by blood vessel abnormalities.
