INFLAMMATION

Question 1

Inflammation can be best defined as ?

Answer 1

The vascular and cellular response of living tissue to injury

Question 2

The process by which lost or destroyed cells are replaced by vital cells.

Answer 2

Repair

Question 3

Classify this type of inflammation according to its duration:

*** One of relative short duration, lasting for a few minutes, several hours, or one to two days.

*** It is characterized by the exudation of fluids and plasma proteins (inflammatory edema) and by the emigration of leukocytes (predominantly neutrophils).

*** In general, the acute inflammatory response is basically the same regardless of the location or nature of the injurious agent.

Answer 3

Acute inflammation

Question 4

Classify this type of inflammation according to its duration:

*** Usually is characterized by a decline in the vascular contribution (edema and hyperemia) and often by a change in the character of infiltrating leukocytes.

*** Although neutrophilic may be prominent at the inflammatory site, the infiltrate becomes mixed with mononuclear cells (lymphocytes, macrophages and maybe plasma cells) in reasonable numbers.

*** It represents an intermediate time frame that can vary from a few days to a few weeks depending on the nature of the inciting stimulus.

Answer 4

Subacute inflammation

Question 5

Classify this type of inflammation according to its duration:

*** Less uniform than acute inflammation. It is generally of longer duration and is associated with the presence of lymphocytes, macrophages and the proliferation of small blood vessels and fibroblasts.

Answer 5

Chronic inflammation

Question 6

The events in the acute inflammatory reaction are conveniently divided into: (Hint: 3 answers)

Answer 6

• (1) hemodynamic or changes in vascular flow and caliber,
• (2) vascular permeability changes and
• (3) leukocytic exudation.

Question 7

The hemodynamic changes phases is subdivided into three. Name and describe the first part.

Answer 7

Transient Vasoconstriction of Arterioles

*** Vasoconstriction of arterioles occurs immediately following injury. However, this is an inconstant finding. With mild forms of injury, it disappears within three to five seconds. With more severe injury, it may remain for several minutes. The mechanism of this vasoconstriction is unknown, but is probably neurogenic or adrenergic in origin.

Question 8

The hemodynamic changes phases is subdivided into three. Name and describe the second part.

Answer 8

Vasodilatation of Arterioles resulting in Increased Blood Flow

*** Vasodilatation is a constant and fundamental event in the inflammatory process. Initially, it involves arterioles which result in opening of new capillaries and venular beds in the area. Subsequent to vasodilatation, there is increased blood flow to the affected areas (this is the hallmark of the early hemodynamic changes in acute inflammation).

*** Remember, active hyperemia is the first stage of inflammation.
Vasodilatation is induced in part by an axon reflex arc which occurs immediately after tissue injury.

*** Following stimulation of sensory nerve endings at the site of injury, a nerve impulse passes centrally along the axon to its division and then peripherally to the arteriole supplying the injured area. Synaptic vesicles within the adrenergic synapse liberate adrenalin which dilates the peripheral arterioles resulting in increased blood flow to the affected area.

*** The vasomotor nerves are not necessary to the development of dilation or any other aspect of the inflammatory response. Chemical mediators are of more importance in causing vasodilation and are of greater significance in altering vascular permeability.

Question 9

The hemodynamic changes phases is subdivided into three. Name and describe the third part.

Answer 9

Retardation of Blood Flow

*** Slowing of the blood flow to the injured area is brought about by increased permeability of the microvasculature (to be discussed later). The slowing and/or stasis of blood disrupts the laminar flow pattern of the blood and results in the displacement of the cellular elements to the periphery of the microvessels.

*** The leukocytes appear to fall out of the central column of flow and assume positions in contact with the endothelium. When numerous cells adhere to and virtually line the endothelium, the process is referred to as pavementing.

*** These marginated leukocytes stick to the vascular endothelium and eventually migrate through the vascular wall into the extravascular space by a process called emigration which is an active process since leukocytes are motile.

Question 10

By employing special techniques, three general patterns of increased permeability responses can be recognized. These patterns are dependent on the severity of various types of injury and include: (Hint: 3 answers)

Answer 10

• (1) the immediate-transient response,
• (2) the immediate-prolonged response and
• (3) the delayed-prolonged response.

Question 11

Name this pattern of increased permeability response:

Begins immediately after mild injury, reaches it peak by 5 to 10 minutes and phase out within 15 to 30 minutes. The response is elicited by histamine and histamine-like chemical mediators. The venules are the site of increased permeability and leakage (the capillaries are not affected). Vascular leakage result from contraction of endothelial cells which leads to the formation of intercellular gaps.

Answer 11

Immediate-Transient Permeability Response

Question 12

Name this pattern of increased permeability response:

Begins immediately after injury, is sustained at a high peak for several hours and continues for one to several days until the damaged vessels are thrombosed or repaired. The response is encountered with severe injury (usually associated with necrosis of endothelial cells). Increased permeability and vascular leakage occur at all levels of the microcirculation, including venules, capillaries and arterioles. The mechanism for increased permeability appear to be “direct damage” to the vascular endothelium.

Answer 12

Intermediate-Prolonged Permeability Response

Question 13

Name this pattern of increased permeability response:

occurs after a period of delay (latent period of 6-12 hours) and lasts for several hours or days (the duration of the latent period and the time of peak permeability vary with the form of injury). This response occurs after mild to moderate thermal injury, or x-ray or ultraviolet irradiation, with certain bacterial toxins and in delayed hypersensitivity reaction. It is believed that the delayed leakage is largely due to direct injury to the endothelium by the injurious agent. However, electron microscopy studies show the leakage to occur between endothelial cells, somewhat similar to that produced by histamine, but there is no endothelial cell contraction. Why intercellular gaps form with this type of direct injury and why the leakage is delayed is unknown. Increased permeability and leakage occur in both venules and capillaries.

Answer 13

Delayed-Prolonged Permeability Response:

Question 14

Refers to the massing of leukocytes, principally neutrophils and monocytes (macrophages), in sites of inflammation. The phagocytic leukocytes engulf and destroy or, at least, weaken foreign invaders

Answer 14

Leukocytic exudation

Question 15

The sequence of events by which leukocytes aggregate and act at the inflammatory site can be considered under the following headings: (Hint: 4 answers)

Answer 15

• (1) margination and pavementing,
• (2) emigration,
• (3) chemotaxis and
• (4) phagocytosis.

Question 16

Refers to the process by which motile leukocytes escape from the blood vessel lumen into the perivascular tissues (neutrophils, basophils, monocytes and lymphocytes all use the same pathway).

Answer 16

Emigration

Question 17

_______ or the peripheral orientation of leukocytes in the slow-moving bloodstream was mentioned in the discussion of “hemodynamic changes.” Basically, slowing or stagnation of blood disrupts the normal laminar pattern of flow and cellular elements fall out of the central column to assume positions in contact with the endothelium. Subsequently, leukocytes adhere to the endothelial wall (_______). This displacement of leukocytes toward the periphery of the bloodstream is apparently governed by the laws of physics.

Answer 17

Margination; pavementing

Question 18

Defined as the unidirectional migration of leukocytes toward an attractant. Thus, leukocytes are drawn to the site of injury by chemotactic influences which may be exogenous or endogenous. All granulocytes, monocytes and, to a lesser extent, lymphocytes respond to such chemoattractants.

Answer 18

Chemotaxis

Question 19

Neutrophils are attracted primarily by two chemotactic agents namely?

Answer 19

o (1) bacterial products and
o (2) products of the complement system.

*** Soluble bacterial factors with chemotactic activity can be isolated from filtrates of a variety of organisms (E. coli, Staphylococcus aureus, etc.). Also, bacterial proteases can generate chemotactic activity by cleaving the C3 and C5 fragments, C3 fragment and C5,6,7 fragments.

Question 20

Refers to the engulfment of foreign particulate matter by phagocytic cells, particularly by neutrophils and macrophages.

Answer 20

Phagocytosis

Question 21

Phagocytosis involves three distinct but interrelated steps namely ?

Answer 21

o (1) recognition,
o (2) engulfment and
o (3) killing and/or degradation.

Question 22

Two categories of bactericidal mechanisms recognized in neutrophils

__________ Mechanisms are initiated by a burst of oxidative activity during phagocytosis. This results from activation of a plasma membrane linked oxidase that converts oxygen (O2) to hydrogen peroxide (H2O2). It is now believed that various toxic byproducts of such oxygen are the killers of ingested bacteria. The toxic products that have been most widely studied are hydrogen peroxide and superoxide ions.

Answer 22

Oxygen-dependent Bactericidal Mechanisms

Question 23

Two categories of bactericidal mechanisms recognized in neutrophils

Effective in killing bacteria, fungi, viruses and mycoplasma. During phagocytosis, reduced pyridine nucleotide oxidase is activated, resulting in the liberation of hydrogen peroxide within the phagolysosome.

Answer 23

Hydrogen-Peroxide-Myeloperoxidase-Halide System

*** This hydrogen peroxide in the presence of myeloperoxidase (an enzyme found in lysosomes of neutrophils) and a halide ion (such as chloride, iodide or bromide) is effective in killing phagocytized organisms.

Question 24

Oxygen-Independent Bactericidal Mechanisms include the following: (Hint: 3 answers)

Answer 24

o (1) hydrogen ions derived from increased production of lactate or from the action of carbonic anhydrase result in a marked reduction of pH within phagolysosomes (few bacteria can continue to grow at a pH of 4.0 or less and many are actually killed by lactic acid).
o (2) lysozyme action which attacks bacterial cell walls, especially those of gram-positive cocci, by hydrolyzing the muramic acid-N-acetyl glucosamine bond which is found in the glycopeptide coat of all bacteria.
o (3) Arginine-rich cationic proteins found in neutrophils can lyse bacterial membranes. Although most organisms are killed by phagocytes (neutrophils and monocytes), some are virulent enough to destroy such cells. Also, there are organisms (tubercle bacilli, etc.) which survive within phagocytes.

Question 25

Free radical generated during the conversion of oxygen to hydrogen peroxide in the phagosomes. There is evidence that this reactive radical alone is toxic to microorganisms.

Answer 25

Superoxide anion

Question 26

Name this chemical mediator of inflammation with the given data: * Contained within and released from granules of mast cells (also released from basophils and platelets). * It induces dilatation of arterioles and increased permeability of venules and capillaries. * Exerts its effect almost exclusively in early inflammatory responses. Its action is relatively brief and occurs primarily during the intermediate-transient response induced by mild injury.

Answer 26

Histamine

Question 27

Name this chemical mediator of inflammation with the given data: Has actions similar to those of histamine in some species (rodents). It is also released from mast cell granules.

Answer 27

Serotonin

Question 28

Name this chemical mediator of inflammation with the given data: * Are polypeptides in circulating blood that arise from alpha 2-globulin. Lysis of cells in the injured area (especially leukocytes) releases enzymes which generate _____. * Once generated, the _____ sustain and enhance the early transitory vascular alterations begun by histamine (arteriolar vasodilatation and increased capillary permeability). * In addition, _____ are potent mediators of pain and smooth muscle contraction (arterioles and venules).

Answer 28

Kinins

Question 29

Name this chemical mediator of inflammation with the given data: * Is a self-assembling, extracellular system of serum enzymes that occur in body fluids in association with membranes. T * The _____ sequence is activated by antigen-antibody complexes and by some other large molecules.

Answer 29

Complement

Question 30

Component of complement system that increases vascular permeability. It can be cleaved directly by plasmin, trypsin, bacterial proteases, as well as produced by the classic and alternate pathways.

Answer 30

C3 component

Question 31

Component of complement system that increases vascular permeability (being more potent than C3). It is also chemotactic to neutrophils and macrophages.

Answer 31

C5 component

Question 32

Component of complement system that chemotactic for neutrophils and macrophages, but it has no permeability effect.

Answer 32

C5,6,7 complex

Question 33

Name this chemical mediator of inflammation with the given data: * Are 20-carbon chain unsaturated fatty acids that exert enhancing or depressant effects on numerous biological processes (including inflammation). * The inflammatory stimuli induce ______ synthesis and release. * In inflammation, ______ contribute to the genesis of vasodilatation, increased permeability, fever and pain.

Answer 33

Prostaglandins

Question 34

Name this chemical mediator of inflammation with the given data: * Of neutrophils (cationic proteins, acid proteases, neutral proteases) have numerous and profound effects on the inflammatory process. * They may serve to increase vascular permeability and chemotaxis.

Answer 34

Lysosomal enzymes

Question 35

Name this chemical mediator of inflammation with the given data: * Are referred to as lymphokines and they are produced by the sensitized T-lymphocytes associated with cell-mediated immunity. * The lymphokines induce a variety of activities, including chemotaxis of macrophages, neutrophils and basophils as well as inhibition of macrophage migration.

Answer 35

Lymphocyte factors

Question 36

Give the morphology, origin, conditions encountered, and function of neutrophils.

Answer 36

Morphology: Neutrophils are 10-12 microns in diameter and have nuclei which are band-shaped or have three to five lobes. In tissue sections, the nuclei usually stain intensely with hematoxylin. The cytoplasm is irregular and may not be seen with H & E. If observable, the cytoplasm tends to be eosinophilic. In blood smears, the cytoplasm of neutrophils contains granules which are lavender. These granules (which are not usually apparent in tissue sections), correspond to the lysosomes and they are rich in proteolytic enzymes. Neutrophils are actively motile and phagocytic. Origin: Neutrophils originate from myeloid tissue of the bone marrow. They are attracted to injured areas by chemotactic substances and do not reproduce at the inflamed sites. Conditions encountered: Neutrophils constitute the "first line of cellular defense" against invading organisms and particulate material. They are the first to gather in acute inflammation. Neutrophils are seen in response to pyogenic organisms and are the principal constituent of pus. Remember, the number of neutrophils in the circulation increases greatly in the early stages of inflammation. Function: All of the neutrophil's characteristic cell activities participate in the inflammatory response. These include * (1) phagocytosis, * (2) production of proteolytic and lipolytic enzymes to digest bacteria, dead cells, etc., * (3) they may produce substances which neutralize the toxic products of bacteria and * (4) they may act as an energy source for other cells (there is evidence that neutrophils shed their cytoplasm which is then transferred to "mononuclear cells" as an energy source).

Question 37

Give the morphology, origin, conditions encountered, and function of eosinophils.

Answer 37

Morphology: The eosinophil is 10-15 microns in diameter. In tissue sections, it has a nucleus which is usually bilobed and does not stain as intensely as the nucleus of the neutrophil. The cytoplasmic granules are larger and more eosinophilic than those of neutrophils. The eosinophil of the horse has the largest granules among domestic animals. This cell is motile, phagocytic and attracted by chemotactic substances. Origin: The eosinophil originates in the myeloid tissue of bone marrow and does no reproduce at the site of inflammation. Conditions encountered: The eosinophil may appear early and/or late in inflammation. It is most prominent in conditions where there is no immune response (hay fever and asthma in man, parasitic conditions, etc.). The eosinophil is especially prominent in * * (1) the secondary invasion of parasites in a tissue, * (2) in the brain of pigs with salt poisoning and * (3) in so-called eosinophilic myositis of cattle. Function: The true functions of the eosinophil are unknown. Their biologic activities resembles, to some degree, those of neutrophils. They are motile, respond to chemotactic agents and are also phagocytic (although to a much lesser degree than are neutrophils). In hypersensitivity reactions, it has been suggested that eosinophils serve to degrade chemical mediators (especially histamine) and terminate the allergic reactions (i.e., eosinophil granules contain histinase). The phagocytic function may be of importance, especially the phagocytosis of antigen-antibody complexes. Another possible function is the production of fibrinolysin.

Question 38

Give the morphology, origin, conditions encountered, and function of basophils and mast cells.

Answer 38

Morphology: In blood smears, the basophil is 10-12 microns in diameter and contains blue granules (with Giemsa or Wright stain). The cell is slowly motile and not phagocytic. Basophils are present in blood in very small numbers and they are seldom seen as a prominent part of the inflammatory reaction. Morphologically, basophils have large lobulated nuclei and their granules contain heparin and histamine but no acid hydrolases. There remains no convincing evidence that the mature circulating basophil represents a precursor of mature tissue mast cells. Mast cells are granular connective tissue cells found throughout the connective tissues in virtually every organ, principally in perivascular sites. They have mononuclear nuclei, are slightly larger, and have somewhat more abundant cytoplasm than the basophil. Their granules contain heparin, histamine and other proteolytic enzymes. In some animals they also are rich in serotonin. Function: The true functions of basophils are unknown. However, both basophils and mast cells release pharmacologically active compounds (heparin/histamine) in response to antigen-antibody complexes (as well as trauma and drugs). The immunoglobulin IgE binds selectively to the surfaces of mast cells and basophils and interaction of this antibody with specific antigens trigger degranulation and the release of histamines and other mediators. Mast cells are intimately involved in the pathogenesis of acute inflammation since it is their release of histamine which triggers many of the manifestations arising from smooth muscle contraction and edema formation.

Question 39

Give the morphology, origin, conditions encountered, and function of lymphocytes.

Answer 39

Morphology: The mature lymphocyte is 7 10 12 microns in diameter, but larger lymphocytes may range up to 16 microns or more in diameter. The nucleus is round to somewhat oval and the nuclear membrane is thinner than that of the other inflammatory cells. Heavy chromatin granules are present within the nucleus and these often tend to be marginated just under the nuclear membrane. Their nucleoli usually are masked by the heavy clumps of chromatin. In tissue sections, the cytoplasm, if visible, consists of a narrow rim which may or may not completely surround the nucleus. The cytoplasm is homogeneous, pale blue and may contain a few azurophilic granules. Larger lymphocytes have more cytoplasm. Lymphocytes are slightly ameboid, but they are not phagocytic. Origin: Lymphocytes originate in lymphoid tissue, such as lymph nodes, spleen and thymus, and are carried to the site of inflammation by the blood. In addition, some lymphocytes are produced in bone marrow and there is some reproduction at the site of inflammation. Circulating small lymphocytes represent at least two different functional populations of lymphoid cells (however, they cannot be distinguished structurally). These thymic-derived lymphocytes (T-lymphocytes) and bone marrow-derived lymphocytes (B-lymphocytes) are differentiated on the basis of life-span, their response to mitosis-inducing drugs and the reactivity of their cell membranes in immunologic reactions. B-lymphocytes represent the precursors of plasma cells which form antibody. Following contact with an appropriate antigen, these lymphocytes become transformed into large "blast" cells (plasmablasts). The T-lymphocytes are associated with cell-mediated reactions involving the direct interaction of small lymphocytes and foreign proteins. The immunologic reaction is represented in tissues as lymphocytic "exudate" (lymphocytic perivascular cuffing). The small T-lymphocyte may transform into large lymphocytes (activated T-lymphocytes that act by secreting lymphotoxins and lymphokines). Conditions encountered: Lymphocytes appear late in inflammation. The arbitrary time of 48 to 72 hours is usually given as the time of appearance. They are seen as a prominent part of long-standing inflammatory reactions. Viral infections, particularly those of the central nervous system, are often associated with lymphocytes. In the brain and spinal cord, lymphocytes tend to accumulate around blood vessels (perivascular cuffing). The number of lymphocytes is under the control of endocrine secretions from the pituitary and adrenal cortex. Some of the glucocorticoids cause a decrease in the circulating lymphocytes and eosinophils. They also have an anti-inflammatory effect by decreasing the accumulation of lymphocytes and other inflammatory cells in the tissue. Function: It is generally agreed that lymphocytes function primarily in the immune response (including both the humoral and cell-mediated immunity). The T-lymphocytes form the major portion of circulating lymphocytes. They have the capability of recirculating from lymphoid tissue to the thoracic duct, to the circulating blood and back to lymphoid tissue. These cells are involved in cell-mediated immunity. The B-lymphocytes are found in the blood, but do not recirculate. They are found in lymphoid tissues and are responsible for antibody synthesis (along with plasma cells). Other less well-defined functions have also been attributed to lymphocytes.

Question 40

Give the morphology, origin, conditions encountered, and function of plasma cells.

Answer 40

Morphology: The plasma cell is about 12 to 15 microns in its greatest diameter. The nucleus is similar to that of lymphocytes, although the arrangement of the chromatin tends to resemble more nearly the typical "cartwheel" of "clock-face" (with the large chromatin mass in the center of the nucleus surrounded by other masses just beneath the nuclear membrane). The nucleus is usually eccentrically located in the cell. The cytoplasm is more abundant than in lymphocytes and tends to be more basophilic. There is usually a clear space or halo near the nucleus which corresponds to the Golgi complex. The plasma cell is said to be slightly ameboid and slightly phagocytic. Origin: Plasma cells originate from lymphocytes. Under an appropriate antigenic stimulus, small lymphocytes (B-cells) transform into larger "blast" cells which, in turn, develop into plasma cells. Once the plasma cell is formed, there is no evidence of reproduction. Function: Plasma cells are committed to antibody production. Following excretion of globulin, most lyse and die.

Question 41

Give the morphology, origin, conditions encountered, and function of macrophages.

Answer 41

Morphology: Macrophages vary in size (from 12 to 20 microns or more in diameter). The nucleus is round to oval and the nuclear membrane is relatively thin. There are fine to medium chromatin granules in the nucleus. One to two nucleoli can usually be seen. There is abundant homogeneous, eosinophilic cytoplasm. Macrophages may "bunch" together and resemble epithelium, thus the term "epithelioid cells." The macrophage is actively ameboid and actively phagocytic. Origin: There is evidence that macrophages originate from blood monocytes. Monocytes emigrate from the blood into the inflammatory lesions and immediately transform into macrophages. Even though some macrophages may originate from lymphocytes, the majority of those that accumulate in inflammation are derived from blood monocytes. Function: The primary function of macrophages is phagocytosis and they are termed the "second line of cellular defense." They are also capable of pinocytosis of soluble molecules. Thus, the function of macrophages in the inflammatory process include the following: * a.Phagocytosis and digestion of invading organisms or foreign particles. * b.Release potent enzymes that may degrade connective tissue. * c.Release chemotactic and permeability factors that may prolong inflammation. * d.Release substances responsible for leukocytosis and fever (prostaglandins, endogenous pyrogens). * e.Release factors that aid in wound healing. * f.Secrete proteins that are important in defense mechanisms (lysozymes, interferon). * gServe to process antigens in cell-mediated immune reactions.

Question 42

Give the morphology, origin, conditions encountered, and function of giant cells.

Answer 42

Inflammatory giant cells are multinucleated cells that result from the fusion of monocytes and/or macrophages. However, giant cells may form by mitotic division of the nuclei without division of the cytoplasm. In giant cells, the nuclei may be clustered in the center of the cell or arranged in a "ring" fashion around the periphery. The finding of giant cells in lesions usually suggest the possibility of diseases involving fungi, mycobacteria or some foreign body (they are associated with large amounts of indigestible material).

Question 43

Name this type of exudation with the given data: *** characterized by the outpouring of a low-protein fluid. (This is so-called inflammatory edema and the protein content is higher than that of non-inflammatory edema *** composed primarily of a slightly cloudy fluid. Its presence usually indicates mild injury. However, this type of exudate is seen in the early stages of most acute inflammatory reactions. *** Microscopically, it appears as a homogeneous, slightly eosinophilic material. It functions to dilute the irritant and to bring antibodies into the inflamed area. The skin blister that results from a burn is a simple example of this exudate. *** This exudation along with hyperemia represents the "first" stage of pneumonia.

Answer 43

Serous exudation

Question 44

Name this type of exudation with the given data: *** Is characterized by the presence of fibrin as the major constituent. It occurs in the more severe inflammations which permit the escape of large fibrinogen molecules from the blood vessels (a fibrinous exudation is indicative of severe vascular damage). *** Occurs chiefly on mucous and serous membranes, including the alveolar surfaces of the lungs. Masses of fibrin on an epithelial surface are referred to as follows:

Answer 44

Fibrinous exudation

Question 45

Refers to masses or layers of fibrin which can be peeled away from the surface quite easily, leaving an intact epithelial membrane.

Answer 45

Croupous membrane (pseudomembrane)

Question 46

Refers to masses or layers of fibrin which are quite firmly attached to the underlying tissue (when removed, the underlying tissue torn).

Answer 46

Diphtheritic membrane

Question 47

Name this type of exudation with the given data: *** characterized by the presence of pus (neutrophils mixed with cellular debris). *** usually caused by pyogenic or pus-forming bacteria (Corynebacterium pyogenes, Pseudomonas aeruginosa, etc.)

Answer 47

Suppurative exudation

Question 48

Refers to a focal or circumscribed collection of pus

Answer 48

Abscess

Question 49

Multiple collections of pus scattered throughout the body

Answer 49

Metastatic abscesses

Question 50

Circumscribed collection of pus within or beneath the epidermis.

Answer 50

Pustule

Question 51

Suppurative reaction involving the hair follicles or sebaceous glands.

Answer 51

Furuncle or boil

Question 52

Refers to a diffuse suppurative process, especially one involving the subcutis

Answer 52

Phlegmon (cellulitis) *** tends to spread indefinitely, whereas an abscess is usually confined.

Question 53

Refers to the presence of pus in preformed body cavities, usually serous cavities (pyothorax, pyoperitoneum, etc.).

Answer 53

Empyema

Question 54

Refers to pus in the uterus

Answer 54

Pyometria

Question 55

Refers to pus in the uterus

Answer 55

Pyoderma

Question 56

Refers to pus in the cerebral ventricles

Answer 56

Pyocephalus

Question 57

Refers to a condition in which pyogenic organisms travel from one part of the body to another by way of the bloodstream and set up secondary sites of suppuration (metastasis).

Answer 57

Pyemia

Question 58

Name this type of exudation with the given data: *** Occurs whenever some form of severe injury causes rupture of vessels or diapedesis of erythrocytes. *** not a distinctive form of exudation. It is almost always a basic fibrinous or suppurative exudation accompanied by the extravasation of large numbers of erythrocytes.

Answer 58

Hemorrhagic exudation

Question 59

Name this type of exudation with the given data: *** Characterized by excessive mucin *** Limited to mucous membranes since it is secreted by goblet cells. *** Grossly, appears as a clear or cloudy tenacious fluid on the mucosal surfaces. The increased mucin serves to protect damaged mucosal surfaces.

Answer 59

Catarrhal exudation

Question 60

What are the local clinical signs of acute inflammation?

Answer 60

1. Heat - dilation of the microcirculation and increased blood flow into the injured area 2. Redness - dilation of the microcirculation and increased blood flow into the injured area 3. Swelling - produced largely by the escape of fluid, plasma proteins and cells from the blood into the perivascular tissue. 4. Pain - somewhat obscure, but the best evidence suggests that overt pain can be induced by the prostaglandins as well as bradykinin. Also, pain may be caused by increased tissue pressure due to the inflammatory exudate. 5. Loss of function