What are the characteristics of inflammation?
- involves changes in vascular bed, blood, connective tissue
- intended to eliminate irritant and repair damaged tissue
What is the purpose of inflammation?
- contain and isolate an injury
- destroy invading microorganisms anr/or inactivate toxins
- acheive healing and repair
What are the 3 outcomes of inflammation?
- ideal conditions return to normal
- intense inflammatory response in an attempt to separate the injured tissue
- failure to eliminate cause of inflammation
What happens in ideal inflammatory reactions?
- elimination of the source of injury
- resolution of inflammatory process
- restoration of normal tissue architecture and physiologic functions
What occurs in an intense inflammatory response?
the body attemps to isolate the inflammatory process by a formation of a wall/capsule
What happens if there is failure to eliminate the causative agent?
- persistence of inflammatory cells and formation of scar tissue
How do you classify inflammation?
- type of exudate
- tissue/organ affected
what are the main characteristics of peracute inflammation?
- caused by a potent stimulus
- the animal has no time to respind
- less common
What is the vascular involvement of peracute inflammation?
- slight edema
- minimal hemorrhage
What is the vascular involvement in acute inflammation?
- active hyperemia
- occasional fibrin thrombi within vessels
what are the predominant cells in acute inflammation?
neutrophils, sometimes with lymphocytes and plasma cells
What are the clinical signs of acute inflammation?
- calor, rubor, tumor, dolor, and loss of function
What is the lymphatics role in acute inflammation?
moving away the exudate
- can lead to acute regional lymphadentitis
What is the problem with lymphadenopathy?
do not know if the inc. in size is due to inflammation or neoplasia
What is subacute inflammation?
defined as a gradual change between acute and chronic
- is used with the inflammatory response does not include reparative responses such as fibroplasia and angiogenesis
What is the vascular involvement in subacute inflammation?
- decline in magnitude of the vascular changes
- less hemorrhage, hyperemia, and edema
What are the cells of subacute inflammation?
neutrophilic with lymphocytes macrophages and plasma cells
What is chronic inflammation?
result of persistent inflammatory stimulus in which the host has failed to completely eliminate the causative agent
What is the vascular involvement in chronic inflammation?
chracterized by proliferation of cappilaries and small blood vessels resulting in hemorrhage and congestion
What are the predominant cells in chronic inflammation?
lymphocytes, macrophages, plasma cells, and fibroblasts
What is chronic active inflammation?
chronic inflammation may be accompanied by acute exacerbation in which the tissues exhibit all of the usual characteristics of chronicity, with features of acuteness superimposed
what are the cells present in chronic active inflammation?
neutrophils, inflammatory cells associated with chronic inflammation, and host responses such as fibroplasia and angiogenesis
What is locally extensive inflammation?
involves a considerable zone of tissue within an inflamed organ
What is exudation?
escape of fluid, proteins and blood cells from the vascular system into the interstitium or body cavities
What is exudate?
inflammatory extravascular fluid that has a high protein conc., much cellular devris, and a specific gravity above 1.020
What is a transudate?
an ultrafiltrate of blood plasma and results from hydrostatic imbalances across the vascular endothelium
- low protein content
- specific gravity less than 1.020
What is edema?
an excess of fluid in the interstitial tissue or serous cavities
- can be an exudate or transudate
What is serous exudation?
inflammatory process in which the outpouring of thin fluid, originating from plasma or secretions of mesothelial cells, occurs in tissues in the absence of a prominent cellular response
What is the gross appearance of serous exudate?
yellow, straw-like color, fluid commonly seen in very ealy stages of inflammation
- thin and watery
- ulceration will follow the rupture of a vesicle
What is an ulcer?
a local defect of the surface of an organ or tissue in which the epithelial surface is denuded beyond the basement membrane
What is an epidermal erosion?
moist, circumscribed, usually depressed lesion due to loss of all or part of the epidermis. Is shallow and does not penetrate into the dermis
What is a skin ulcer?
a circumscribed area of skin loss extending through the epidermis and at least part of the dermis
What is a vesicle?
- a sharply circumscribed, elevated lesion that is less than 5mm in diameter containing serous fluid
What is fibrinous exudation?
severe injury to endothelium and basement membranes results in leakage of large plasma proteins including fibrinogen, which polymerizes perivascularly as fibrin
What is the gross appearance of fibrinous inflammation?
yellow-white, or pale tan, stringy, shaggy meshwork which gives a rough irregular appearance to the tissue surfaces
- friable material peels off easily
What is pus?
a liquid inflammation product composed of:
- accumulated dead cells
- variable numbers of viable cells (neutrophils)
- fluid added by the inflammatory edema-forming process
What is suppuration?
the process by which pus is formed
- implies that neutrophils and proteolytic enzymes are present and the necrosis of host tissue cells has occured
What is an abscess?
is a circumscribed (partially walled off) collection of pus. A localized form of suppurative inflammation
What is the gross appearance of an abscess?
is yellow-white to gray-white and varies from watery to viscous depending on the fluid content
What is fibrinopurulent exudate?
used to classify an inflammatory process in which neutrophils and fibrin are abundant
What is granulomatous inflammation?
an inflammatory response characterized by the presence of lymphocytes, macrophages, and plasma cells with the predominant cell being the macrophage
What is a granuloma?
macrophages are clustered on a characeristic elliptical formation around the causative etiologic agent, or around a central necrotic area, or simply as organized nodules
What is the etiology of granulomatous inflammation?
usually some non-digestible organism or particle which serves as a chronic inflammatory stimulus, and induces delayed- type hypersensitivity
What microorganisms cause granulomatous inflammation?
mycobacterium, actinomyces, blastomyces, coccidioides
What are some noninfectious agents that cause granulomatous inflammation?
mineral oil. complex polysaccharides, foreign bodies
What is mucopurulent or catarrhal inflammation?
the inflammatory exudate is composed of mucus and pus
What is major basic protein?
component of eosinophil granules
- is strongly toxic to parasites as well as other kinds of cells