INFLAMMATION

Inflammation is defined as the local response of living tissues to injury due to any agent.

Inflammation is body defence reaction in order to alteration or limits the spread of injurious agent.

Causes: Physical agents (heat, cold, radiation, mechanical injury). Chemical agents (organic and inorganic poisons).Infective agents (bacteria, viruses, parasites).Immunological agents (cell-mediated and antigen-antibody reactions).

Clinical-morphological signs of inflammation: rubor (redness); tumor (swelling); calor (heat); dolor (pain);functio laesa (loss of function).

Inflammation of an organ is usually named by adding the suffix- 'itis' to its Latin name, e.g. appendicitis, hepatitis, cholecystitis, meningitis, etc.

Phases of inflammation: alteration, exudation,proliferation.

1st phase alteration degeneration and necrosis of the cells, tissue.microcirculatory bed reaction with disturbance of blood rheology, increased vascular permeability, exudation of main blood components, emigration of blood cells, phagocytosis, formation of exudation,development of inflammatory infiltration.2nd phase exudation formation of exudate.3d phase proliferation, which leads to restoration of tissue.

Classification According to prevailing one of phases of inflammation exudative,proliferative. According to the defense capacity of the host and duration of the responseacute,chronic.

Acute inflammation is of short duration and represents the early body reaction and is usually followed by repair.

Chronic inflammation is of longer duration. It occurs in case when the causative agent of acute inflammation persists for a long time. Besides, some stimulus induce chronic inflammation from the beginning.

Morphological manifestations of inflammation depend on a number of factors and processes:factors of the organisms,factors of the host, type of exudation, cellular proliferation.

Factors of organisms:Type of injury and infection. Virulence. Dose. Portal of entry. Product of organisms.

Factors of host:General health of host. Immune state of host. Leucopenia. Site or type of tissue involved.Local host factors.

Morphology of acute inflammation

Exudative inflammation is characterized by prevailing of exudation and development of exudates in tissue and body cavities.

Morphological types of exudative inflammationSerous, when the fluid exudate resembles serum or is watery. Fibrinous, when the fibrin content of the fluid exudates. It can be croupous and diphtheritic. Purulent or suppurative exudate is formation of pus in infection with pyogenic bacteria.Hemorrhagic, when there is vascular damage.Catarrhal, when the surface of epithelium in case of inflammation produces increased amount of mucus.MixedAnaerobic(according to character of exudates and prevailing location):

Serous inflammation exudate is not quite clear fluid and contains about 2% of proteins with a bit of neutrophils,arises in body cavities, mucous, meninx and internal organs and skin,causes some infective agents (mycobacterium tuberculosis, meningococcus), physical and chemical agents, autointoxication (in case of uremia),outcomes: resolution (usually), sclerosis (very seldom).

Fibrinous inflammationexudate looks like white-grey membrane on the surface of organs or mucous, microscopically eosinophilic meshy mass or amorphous coagulating mass,appears more often in body cavities and mucous,causes streptococci, staphylococci, corynebacterium diphteriae and shigella, autointoxication,outcomes: sclerosis (usually), resolution (very seldom).

Types of fibrinous inflammation according to the type of epithelium on which inflammatory process develops and depth of necrosis:croupous develops on columnar epithelium, serous membranes (fibrinous membranes unfix easily, without any effort).diphtheritic develops on squamous or intermediate epithelium (fibrinous membranes unfix with difficulties).

Croupous or diphtheritic inflammation possible in GIT and endometrium depending on deepness of necrosis:-superfitial necrosis croupous,-deep diphtheritic.

Fibrinous colitisIntraluminal fibrinous exudates Diffused leukocytes infiltration Hyperemia (blood congestion) Deep necrosis

Purulent inflammation exudate (pus) is creamy or opaque in appearance and is composed of numerous dead as well as living neutrophils, some red cells, fragments of tissue debris and fibrin,develops in any tissue and organs,causes pyogenic bacteria,outcomes: sclerosis (may be petrifaction), generalization, resolution (very seldom).

Types of suppuration: abscess focal purulent inflammation with following formation of cavity, which contains purulent exudate, phlegmon unbounded purulent inflammation in which pus spreads diffusely between different components of tissue owing to fusion and tissue lysis, empyema purulent exudate accumulation in human closed cavities or cavities with bed drenage, furuncle acute inflammation via hair follicles in the dermal tissues, carbuncle located abscess in dermis and soft tissues of neck, cellulitis diffuse inflammation of soft tissues resulting from spreading effects of substances like hyaluronidase released by some bacteria, bacterial infections of the blood.

Outcomes of acute inflammatory process:resolution complete return to normal tissue, occurs when tissue changes are slight and the cellular changes are reversible,healing by scarring (organization) takes place when tissue destruction is extensive so that there is no tissue regeneration, progression to suppuration,progression to chronic inflammation.

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