Chapter 15 Microbial Mechanisms Of Pathogenicity

Front 1

Pathogenicity

Back 1

Ability of microorganism to cause disease by overcoming the defenses of a host

Front 2

Virulence

Back 2

degree or extent of pathogencity

Front 3

Portals of entry

Back 3

Mucous membranes

Skin

Parenteral

Front 4

Mucous membranes

Back 4

Respiratory or GI tract

Front 5

Respiratory

Back 5

Influenza, TB, common cold

Front 6

GI

Back 6

Polio, Hep A, Shigella

Front 7

GU

Back 7

Stds, chlamydia, gonorrhea, syphillis

Front 8

Skin

Back 8

Unbroken skin is imprentable to most microganisms.

Hookworm and syphillis penetrate

Front 9

Parenteral

Back 9

Deposited into tissues by punctures, injectiosn, bites, cuts, wounds, surgery

Front 10

Preferred portal of entry

Back 10

pathogens have a preferred entry route that is requried for the organism to cause disease

Front 11

Intectious dose

Back 11

number of orgnaisms needed to cause disease

Front 12

Adherence or Attachment

Back 12

Pathogens must have a way of attaching to host tissues at the portal of entry

Front 13

Virulence factors

Back 13

Capsules, cell wall components, enzymes, antigenic variation, penetration into cytoskeleton

Front 14

Capsules

Back 14

Impairs phagocytosis

Front 15

Strep pyogenes cell wall component

Back 15

M protein that mediates attachment to host epitelial cells and help resist phagocystosis

Front 16

Mycobacterium tuberculosis cell wall component

Back 16

Waxy substance in the cell wall that resists digetion by phagocytes

Front 17

Coagulases

Back 17

Clot production, walls off the bacteria and prevent phagocytosis and isolates the microbe form other host defenses

Front 18

KInases

Back 18

Break down clots, and allow invsion into the tissues

Front 19

Collagenase

Back 19

Breaks down collagen allowing spread of organsism

Front 20

Antigenic variation

Back 20

Abiltiy of an organism to alter surface antigens so that antibodies against that organism are no longer effective

Front 21

Penetration of cytoskeleton

Back 21

Penetration into the host cell or the ability to move through and between host cells

Front 22

How pathogens damage host cells

Back 22

By using the hosts nutrients

Direct damage

production of toxins

Exotoxin and endotoxins

Front 23

Direct damage

Back 23

Multiplying within the host cell and the host cell will then rupture

Front 24

Exotoxin

Back 24

Prdocued wihtin bacteria and secreted to the outside. easily differense into the blood and rapdily transported throughout the body

Responsible for disease specific signs and symptoms

Body produces antibodies to toxins

Front 25

Botulism exotoxin

Back 25

Neurotoxin prevents transmission of nerve impusles resulting in flaccid paralysis

Front 26

Tetanus exotoxin

Back 26

Neurotoxin blocks nerve impulses to muscle relaxation resulting in uncontrollabel muscle contractions

Front 27

Staph food poisoning exotoxin

Back 27

Enterotoxin - secretion of fluids and electrolytes resulting in diarrhea

Front 28

Diptheria exotoxin

Back 28

Cytotoxin - inhibits protein synthesis

Front 29

Endotoxin

Back 29

Part of outer cell walls of Gram - bacteria. Released when bacteria die, lysing cell walls

Produces same signs and symptoms regardless of microbes

Front 30

shock

Back 30

any life threatening decrease in blood pressure

Front 31

septic shock

Back 31

caused by bacteria

Front 32

endotoxic shock

Back 32

caused by gram - bacteria

Front 33

Portals of exit

Back 33

Microbes leave via specific routes

Secretions, excretions, discharges, shed tissue