Cough with weight loss is usually one of the symptoms of tuberculosis, a chronic infectious disease caused by Mycobacterium tuberculosis, which can affect many organs, with tuberculosis infection of the lungs being the most common. The most common form of tuberculosis infection is in the lungs. People who excrete the bacilli are an important source of infection. Infection with Mycobacterium tuberculosis does not necessarily cause morbidity, but may cause clinical morbidity when resistance is reduced or cell-mediated metaplasia is increased. If diagnosed promptly and treated appropriately, most cases can be cured clinically. The examination items for cough with weight loss are as follows: I. Physical examination: Systemic toxicity symptoms are manifested as low fever in the afternoon, fatigue, loss of appetite, weight loss, and night sweats. When the pulmonary signs progress rapidly and disseminate, there may be high fever and women may have menstrual disorders or amenorrhea. There is a dry cough or only a small amount of mucus. When accompanied by secondary infection, the sputum is mucous or purulent. About 1/3 of patients have varying degrees of hemoptysis. When the inflammation reaches the mural pleura, there is stabbing pain in the corresponding chest wall, which is usually not severe and worsens with breathing and coughing. In chronic severe tuberculosis, respiratory function slows down and dyspnea develops. Second, lung biopsy Lung biopsy is a percutaneous lung biopsy. It is used for the diagnosis and differential diagnosis of peripheral lung lesions or diffuse lung lesions. Its indications are: (1) Mass lesions in the lung that cannot be characterized by fiberoptic bronchoscopy, X-ray, sputum, microbiological blood, etc. It is particularly suitable for the diagnosis of masses located in peripheral areas. (2) Diffuse pulmonary lesions of unknown origin, with percutaneous lung biopsy in the presence of pleural adhesions. (3) Limited pulmonary infiltrates. (4) Mediastinal masses of unknown origin.