Pneumonia is an inflammatory disease of the lungs, characterized by the formation of foci of inflammation and swelling of the lung tissue. The clinical picture of the disease is dominated by signs of intoxication, followed by a cough with a small amount of mucous or mucopurulent sputum, and shortness of breath. When two lungs are affected, bilateral polysegmental pneumonia is observed. The most life-threatening form is miliary (lobular) bronchiolar. Localization in the upper lobes is typical for pneumonia of staphylococcal etiology, in the lower lobes for streptococcal and pneumococcal etiology. Pneumonia caused by pneumococci and staphylococci begins acutely, as a rule, catarrhal forms, and proceeds severely, like lobar pneumonia. With pneumonia caused by mycoplasmas and chlamydia, the process often develops slowly. In some cases, the clinical picture is caused by the development of pneumonitis syndrome; in others, a picture of a respiratory bronchial infection is detected.