Lung nodules are not necessarily calcification may be simple nodules, inflammatory nodules, tuberculosis nodules, lung tumors and other causes, nodules more cases so it is not necessarily caused by calcification. 1. Simple nodules: simple nodules may be caused by vascular lesions, tissue cell proliferation, etc. Patients may have symptoms such as coughing, coughing up sputum, etc., but the symptoms of the disease are not obvious, and more serious patients may have hemoptysis. 2. Inflammatory nodules: Inflammatory lung nodules may be caused by bacterial infection, local soft tissue inflammation and other reasons. Patients may have fever, cough, sputum and other symptoms. 3. Tuberculosis nodules: tuberculosis nodules, also known as pulmonary tuberculosis, may be caused by Mycobacterium tuberculosis infection, and patients may have symptoms such as low-grade fever, fatigue, and lethargy. 4. Lung tumor: Lung nodules may be lung tumors, which are classified into benign and malignant tumors. Lung tumors may lead to calcification in the lung nodules, which may be due to the deposition of calcium salts during the growth of the tumor. 5. Lung calcification: if lung nodules are caused by calcification, chest X-ray will show high-density shadow, and there may be no uncomfortable symptoms, mostly due to pneumonia, tuberculosis, silicosis and other diseases caused by calcium salt deposition in lung tissues. It is recommended that patients wear masks when traveling, and consult a doctor when they find lung nodules to clarify the nature of the lesions, so as not to delay their condition.