66. Fibrinous inflammation: definition, causes, mechanisms, types. Pathological anatomical characteristics, localization, complications, outcomes, clinical significance.

The course of fibrinous inflammation is usually acute. Sometimes (for example, with tuberculosis of the serous membranes) it has a chronic character.

The outcome of fibrinous inflammation of the mucous membranes and serous membranes is different. After the rejection of the films, defects of varying depths remain on the mucous membranes — ulcers. Resorption of fibrinous exudate is possible on serous membranes. However, fibrin masses are often subjected to organization, which leads to the formation of adhesions between the serous sheets of the pleura, peritoneum, and pericardium. In the outcome of fibrinous inflammation, complete overgrowth of the serous cavity with connective tissue may occur — obliteration.

67. Purulent inflammation: definition, causes, mechanisms, types. Pathological anatomical characteristics, complications, outcomes, clinical significance.

With purulent inflammation, neutrophils predominate in the exudate. Decaying neutrophils — purulent corpuscles — together with the liquid part of the exudate form pus, which also contains lymphocytes, macrophages, dead tissue cells, and microorganisms. Pus is a cloudy thick liquid having a yellow-green color. A characteristic feature of purulent inflammation is histolysis, due to the effect of proteolytic enzymes — neutrophils on tissues. Purulent inflammation occurs in any organ and tissue. Morphological picture. Purulent inflammation is an abscess or phlegmon, depending on the prevalence.

An abscess (abscess) is a focal purulent inflammation characterized by the formation of a cavity filled with pus. Phlegmon is a diffuse purulent inflammation in which purulent exudate spreads between tissue elements, impregnating, delaminating and lysing tissues. The causes of purulent inflammation are often pyogenic microbes (Staphylococcus, streptococcus, gonococcus, meningococcus), less often Frenkel's diplococcus, typhoid bacillus, Mycobacterium tuberculosis, fungi. Aseptic purulent inflammation is possible when chemicals enter the tissue.

The course of purulent inflammation is acute and chronic. Acute purulent inflammation, especially in the form of an abscess or phlegmon, tends to spread. Chronic purulent inflammation occurs when the abscess is encapsulated. Sclerosis develops in the surrounding tissues. If the pus finds a way out, a chronic fistula is formed, or a fistula, which opens through the skin to the outside. The outcome of purulent inflammation depends on its prevalence, the nature of the course, the virulence of the microbe and the reactivity of the body. An unfavorable outcome is the generalization of infection with the development of sepsis

68. Catarrhal inflammation: definition, causes, mechanisms. Pathological anatomical characteristics, complications, outcomes, clinical significance.

Catarrhal inflammation, or catarrh, develops on the mucous membranes and is characterized by an abundant release of exudate on their surface (Fig. 5-11). Exudate can be serous, mucous, purulent, hemorrhagic, and it is always mixed with exfoliated cells of the integumentary epithelium. Catarrhal inflammation can be acute and chronic. Acute catarrh is characteristic of a number of infections — acute catarrh of the upper respiratory tract in acute respiratory infection. At the same time, the change of one type of catarrh to another is characteristic — serous catarrh to mucous, and mucous — purulent or purulent hemorrhagic. Chronic catarrh occurs in both infectious (chronic purulent catarrhal bronchitis) and non-infectious (chronic catarrhal gastritis) diseases. Chronic catarrh is accompanied by atrophy (atrophic catarrh) or hypertrophy (hypertrophic catarrh) of the mucous membrane. The causes of catarrhal inflammation are different. Most often, catarrhs have an infectious or infectious-allergic nature. They can develop with auto-intoxication (uremic catarrhal gastritis and colitis) due to exposure to thermal and chemical agents.