What Is Pulmonary Sarcoidosis?

Pulmonary sarcoidosis is a systemic inflammatory condition characterized by the formation of granulomas—tiny clusters of inflammatory cells—in the lungs, often detected during routine CT scans. These granulomas appear as nodular lesions and are typically found in the mediastinum and hilar regions (where the bronchi and blood vessels enter the lungs). While the imaging may resemble lung nodules, it's important to distinguish that pulmonary sarcoidosis is not the same as isolated pulmonary nodules, nor is it a form of cancer. In fact, this condition is classified as a benign, non-malignant disease driven by immune system dysregulation rather than uncontrolled cell growth.

Understanding the Nature of Pulmonary Sarcoidosis

This disorder arises when the body's immune system becomes overactive, leading to the accumulation of immune cells such as lymphocytes and macrophages. These cells clump together to form granulomas, which can affect lung function if they become widespread. Although the exact cause remains unknown, researchers believe genetic predisposition and environmental triggers—such as exposure to certain dusts, chemicals, or infectious agents—may play a role in initiating this abnormal immune response.

How Is It Diagnosed?

Accurate diagnosis is crucial because sarcoidosis can mimic other lung diseases, including tuberculosis or lymphoma. The gold standard for confirming pulmonary sarcoidosis involves obtaining tissue samples through procedures like endobronchial ultrasound-guided biopsy (EBUS) or CT-guided needle biopsy of enlarged lymph nodes. Pathologists then examine the tissue under a microscope to identify non-caseating granulomas—distinctive clusters without central necrosis—which are hallmark signs of sarcoidosis. Imaging tests, blood work (including ACE levels), and pulmonary function tests also support the diagnostic process.

Treatment Approaches and Prognosis

Unlike malignant tumors, pulmonary sarcoidosis usually does not require surgical intervention. Many patients experience spontaneous remission without treatment, especially in mild cases. However, when symptoms such as persistent cough, shortness of breath, or fatigue arise, or when organ function is at risk, treatment becomes necessary. The primary therapy involves corticosteroids like prednisone, administered at an adequate dose and duration to suppress inflammation. In some cases, steroid-sparing agents such as methotrexate or azathioprine may be used for long-term management.

With proper medical care, most individuals respond well to treatment and maintain a good quality of life. Regular follow-ups with chest imaging and lung function assessments help monitor disease progression and prevent complications such as pulmonary fibrosis. Early detection and tailored therapy significantly improve outcomes, making awareness and timely evaluation essential for anyone found to have suspicious nodular changes on lung imaging.