Granulomas in the lung is a noncancerous (benign) inflammation of the lung tissue. It is mostly seen affecting a small area of the lung. Granulomas can occur in other parts of the body, other than the lung. The main cause of lung granulomas is tissue injury, mostly due to an infection. Many times they are detected in x-rays and are often mistaken to be cancer.
Definition of Granulomas
Granuloma is a rough spherical mass of immune cells called the macrophages. These cells are formed when the immune system tries to bar substances that it thinks to be foreign, but cannot eliminate. These substances can be microorganisms like bacteria, fungi, keratinous substances, suture fragments, etc. Thus, it is an inflammatory reaction that occurs in case of infectious and non-infectious diseases.
The term granuloma is loosely referred to as a small nodule that can be a harmless lesion to a malignant tumor. In pathology, granuloma is an organized collection of macrophages. All granulomas contain lymphocytes, neutrophils, eosinophils, multinucleated giant cells, fibroblasts and collagen. They are often spotted in X-rays or CT scans of chest taken for other reasons. The technical definition most widely used to explain a granuloma is "an organized collection of macrophages".
Causes of Lung Granulomas
The granulomas are seen in different infectious and non-infectious diseases. The infections in which granulomas may be seen are:
- Tuberculosis: In this condition, the granulomas of tuberculosis contain caseating tubercles. The non-necrotizing granulomas may also be seen. The multinucleated giant cells or Langhans giant cells with nuclei that looks like an horse-shoe may be present.
- Histoplasmosis: The granulomas may be seen in forms of histoplasmosis. The fungal agent causing this condition are seen within the granulomas after conducting biopsy or microbial cultures.
- Cryptococcosis: The infection of Cryptococcus is seen in people who have a healthy immune system. The granulomatous inflammation seen is due to the encounter of the fungal agent and immune system. These ganulomas in the lung can be necrotizing or non-necrotizing.
- Sarcoidosis: This is a disease whose cause is unknown. The granulomas are seen in many parts and organs of the body. Sarcoidosis disease is common to see granulomans in the lungs and lymph nodes of the chest cavity.
- Chrug-Strauss syndrome: This is a medium and small vessel autoimmune vasculitis that leads to necrosis. This an extremely rare and non-heritable as well as non-transmissible disease.
- Wegener's Granulomatosis: This a form of blood vessel injury that affects the lungs, kidneys and other organs. This is a life-threatening condition that needs long-term immunosuppression.