Chronic inflammation of the left lung can be caused by bronchial foreign bodies, viral infections, bacterial infections, and physiological defects in the structure of the respiratory tract. Depending on the cause of the disease, treatment measures are used, such as surgery, antiviral, and anti-infection. 1. Bronchial foreign bodies: Commonly found in young children, foreign bodies are stuck in the lungs for a long time and form chronic pneumonia, which need to be removed by surgery in time. 2. Viral infection: interstitial pneumonia caused by viral infection is easy to develop into chronic pneumonia if treatment is not timely, the treatment is to strengthen nutrition, bed rest, and the treatment drugs are ribavirin, acyclovir and amantadine. 3. Bacterial infection: Bacterial pneumonia should be selected according to the type of bacteria and drug sensitivity results of antibiotics, such as Streptococcus pneumoniae pneumonia can be used penicillin G, if there are hypoxia and other symptoms, should be given oxygen and other symptomatic treatment. 4. Physiological defects of respiratory structure: commonly seen in children, such as cilia of the respiratory tract morphology and functional developmental abnormalities in the lungs to remove foreign bodies from the trachea to reduce the ability to cause recurrent pneumonia, the evolution of chronic inflammation of the lungs, which often requires regular nebulizer therapy, physical sputum removal of foreign bodies, etc., the physiological defects of the development of the lungs may be improved as they grow older. If chronic inflammation of the left lung is found on examination, further examination should be conducted to clarify the cause of the disease. Chronic pneumonia can be caused by different pathogenic factors, and only when the cause of the disease is clarified can the correct treatment be carried out to achieve the best therapeutic effect.