Fibrous exudate is an exudate characterized by the presence of large amounts of cellulose. When fibrinitis occurs in the plasma membrane and lungs, a small amount of fibrin exudate can be dissolved and absorbed; a large amount of fibrin exudate is prone to mechanization and even occlusion of the plasma membrane cavity, causing organ dysfunction. For example, in fibrinous pericarditis, the two layers of the dirty wall of the pericardium rub against each other due to the heart’s movement, causing the fibrin exuded in the pericardial cavity to become fluffy on the surface of the pericardium, which is called “fluffy heart”. If neutrophils exude less and the protein hydrolase released is relatively insufficient to completely dissolve and absorb the fibrin, it can be mechanized through the growth of granulation tissue and finally lead to fibrosis. What are the easily confused symptoms? Fibrinitis is dominated by the exudation of fibrinogen followed by the formation of fibrin, or fibrin. Fibrinitis occurs easily in mucosa, plasma membrane and lung tissue and needs to be differentiated. 1, occurring in the mucosa Exudate fibrin, necrotic tissue and neutrophils together to form a pseudomembrane, also known as pseudomembranous inflammation. The pseudomembranous inflammation of diphtheria is called solid membrane inflammation if it occurs in the pharynx and does not fall off easily. 2, occurs in the trachea is easier to shed called floating membrane inflammation, easy to cause asphyxiation. 3.Fibrinitis of the plasma membrane can cause fibrinous adhesions in the body cavity, followed by fibrin mechanization and fibrous adhesions. 4, occurs in the lung In addition to a large amount of exuded fibrin, a large number of neutrophils are seen, commonly in lobar pneumonia. Fibrinitis is mostly caused by certain bacterial toxins (e.g., toxins from Bacillus diphtheriae, Bacillus dysenteriae, and S. pneumoniae) or a variety of endogenous and exogenous toxins (e.g., urea and ascending mercury toxicity in uremic syndrome). It often occurs in the mucous membranes (pharynx, larynx, trachea, intestines), plasma membranes (pleura, peritoneum and pericardium) and lungs.