Lobular pneumonia, as opposed to lobar and interstitial pneumonia, is also known as bronchopneumonia, and the essence of the lesion is a very typical purulent respiratory inflammatory reaction. It usually develops as a result of invasion of pathogens into the small airways, for example, after invasion from the ducts of the trachea and bronchi, and then reaches the fine bronchi as well as the terminal fine bronchi, and finally reaches the alveolar mucosa. The whole lung tissue mucosa will appear obvious congestion, edema, and a large amount of purulent inflammatory secretion exudation, manifesting a typical purulent respiratory tract parenchymal reaction, the more common is bacterial infection, so the clinical symptoms will be cough, cough purulent yellow sputum, fever and so on.