Most lung abscesses have an acute or subacute onset, starting with chills, high fever, cough, and coughing up mucus sputum or mucopurulent sputum. If the inflammation spreads to the pleura, there is chest pain. After 1 to 2 weeks, the abscess breaks into the bronchus and suddenly coughs up a large amount of pus sputum, which can be as much as hundreds of milliliters in one day, and the sputum has a foul smell because of anaerobic bacterial infection, and is divided into 3 layers after resting, from top to bottom as foam, mucus and pus residue. After the pus is discharged, the systemic symptoms improve, the body temperature drops, and if effective antibiotics can be applied in time, the lesion can gradually improve within a few weeks, the body temperature tends to be normal, the sputum volume decreases, and the general condition returns to normal. If the treatment is not timely and complete, the medication is not appropriate and adequate, and the body resistance is low, the lesion can gradually become chronic. Some of them break into the chest cavity to form pneumothorax or bronchopleural fistula. At this time, the symptoms are sometimes light and sometimes heavy, mainly coughing, coughing pus sputum, many have hemoptysis, from sputum with blood to hemoptysis, intermittent fever and chest pain, etc. Due to long-term chronic poisoning and consumption, many patients develop emaciation and anemia. Individuals have metastatic abscesses in brain, liver and kidney. Chronic abscesses often have a history of irregular treatment, and the situation is slightly better when the lesion is stable. Signs: early lesions of small extent have no specific signs. Signs of solid lung changes (such as diminished whistling sounds, turbid percussion, bronchial whistling sounds, inspiratory twang sounds) and pleural friction sounds, pleural effusion, pulmonary edema, pneumothorax signs (turbid percussion sounds, mediastinal displacement, diminished whistling sounds at the effusion) can be found, and urn-like whistling sounds are rare. The longer duration of the disease has more pestle fingers, the thorax also has collapsed deformity and poor activity. In cases with pneumothorax and bronchopleural fistula, the corresponding signs are seen on examination.