Right deviation of mediastinum may be caused by enlarged lymph nodes, tumors in the mediastinum, tuberculosis and so on. 1. Enlargement of lymph nodes: Enlargement of lymph nodes is usually caused by reactive proliferation of lymphocytes and histiocytes in the lymph nodes due to various injuries and stimuli, usually due to infections, tumors and other factors. 2. Tumor in mediastinum: mediastinal tumor is a common clinical disease, which may be caused by cells or tissues entering into the mediastinum, etc. Patients may have symptoms such as diaphragm paralysis, hoarse voice and dry cough. 3. Tuberculosis: Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis, usually due to respiratory tract infection, digestive tract infection, etc. The patient may have night sweats (abnormal sweating after going to sleep, and the sweating stops after waking up), fatigue, poor appetite, and emaciation. There are many other causes of right deviation of mediastinum, so it is recommended to clarify the cause of the disease under the guidance of a doctor and avoid blindly using medication on your own.