Lung inflammation is characterized by fever, cough, sputum, chest pain and dyspnea. 1. Fever: one of the most common symptoms, it is a systemic symptom caused by inflammatory mediators in the lungs, and different pathogenic bacteria cause different fever conditions. For example, Streptococcus pneumonia is characterized by high fever, chills, and an episodic fever, i.e., the temperature peaks in the afternoon and evening. 2. Cough: lung inflammation is accompanied by cough, bacterial pneumonia cough with sputum, while mycoplasma pneumonia and viral pneumonia are mostly irritating dry cough. 3. Cough sputum: different pathogenic bacteria sputum is very different. Streptococcus pneumoniae has rust-colored sputum. Staphylococcus pneumonia is purulent sputum with blood in the sputum. Klebsiella pneumoniae has brick-red, jelly-like sputum. However, some pneumonias can have no sputum, such as Mycoplasma pneumonia and viral pneumonia. 4. Chest pain: This is usually characterized by pain in the affected side of the chest, which may radiate to the shoulder or abdomen, and may worsen with coughing and deep breathing. 5. Dyspnea: Lung inflammation leads to dysfunction of lung ventilation and air exchange, and in severe cases, pleural effusion may be present, which affects the systolic and diastolic functions of the lungs and aggravates dyspnea. Sometimes extrapulmonary symptoms such as diarrhea and muscle pain are also present, e.g. Legionella pneumonitis. If you have any of these symptoms, you should seek prompt medical attention to clarify the cause of the disease and take further treatment.