Pathogenesis/Virulence

Question 1

How can diseases be classified

Answer 1

• by the body system they affect
• by the extent of body affected
• by the state of the host when affected
• by their longevity and severity
• by how they are spread to their host

Question 2

True or False

Diseases can only be classified in one way

Answer 2

False

They can be classified in a number of ways

Question 3

In classification, the extent of the body described can be described as either __________ or ___________

Answer 3

Local; systemic

Question 4

In classification, the state of the host when affected can be either ___________ or ___________

Answer 4

Primary; secondary

Question 5

In classification, longevity and severity can be measured by what 4 categories

Answer 5

Acute, chronic, subacute, and latent

Question 6

In classification, diseases spread to their hosts can be either _____________, ____________, ____________

Answer 6

Communicable, noncommunicable, or contagious

Question 7

Acute

Answer 7

Develops rapidly, lasts a short time

Question 8

Chronic

Answer 8

Develops slowly, lasts a long time

Question 9

Subacute

Answer 9

Moderate development, moderate duration

Question 10

Latent

Answer 10

Periodically symptomatic infection

Question 11

Infectious diseases

Answer 11

Diseases caused by microorganisms

Question 12

Communicable

Answer 12

Can be transmitted from one host to another

Question 13

Noncommunicable

Answer 13

Not transmitted between hosts

Question 14

Contagious

Answer 14

Highly communicable

Question 15

Tetanus is an example of a ___________ disease

Answer 15

Noncommunicable

Question 16

Lyme disease is an example of a _______________ disease

Answer 16

Communicable

Question 17

The common cold is an example of a ____________ disease

Answer 17

Contagious

Question 18

Nosocomial infection

Answer 18

Hospital acquired infections

[occur in about 10% of patients]

Question 19

Which populations are more susceptible to nosocomial infections

Answer 19

The young, the old, and the immunocompromised

Question 20

Which bacteria are common culprits of nosocomial infections

Answer 20

• pathogenic cocci (gram + cocci)
• enterobacteria (gram - rods)
• pseudomonas (gram - rods)
• candida (fungus)

Question 21

What are the common nosocomial infections

Answer 21

• Urinary tract
• wounds
• respirator-related pneumonia
• central lines and other catheters

Question 22

Commensal organisms [aka normal flora]

Answer 22

Bacteria that are found in or on our bodies on a semi-permanent basis without causing disease; they provide microbial antagonism

Question 23

Microbial antagonism

Answer 23

Occurs when commensal organisms help prevent bad bacteria from getting into the body

Question 24

Name areas of the body where bacteria should not normally occur

Answer 24

CNS, sinuses, urinary system, lower respiratory tract, blood & other tissues, inner female reproductive system

Question 25

Pathogens

Answer 25

Organisms capable of causing disease

Question 26

Opportunistic pathogens

Answer 26

Commensal or environmental organisms that cause disease under certain circumstances

Question 27

What conditions provide opportunities for pathogens

Answer 27

Changes in the commensal organisms, immune suppression, introduction of commensal or environmental organisms into unusual sites in the body

Question 28

Obligate pathogens

Answer 28

Organisms that must infect a hosts in order to survive; cause disease to accomplish transmission

Question 29

Infection

Answer 29

When an organisms envades body's external defenses, multiplies, and becomes established in the body

Question 30

True or False Infection always causes disease

Answer 30

False Infection does not always cause disease

Question 31

Disease

Answer 31

Results when the infection alters normal body function

Question 32

Symptoms

Answer 32

Subjective characteristics of disease felt only by the patient

Question 33

Signs

Answer 33

Objective manifestations of disease observed or measured by others

Question 34

Pathogenicity

Answer 34

The ability for microorganisms to cause disease

Question 35

Virulence

Answer 35

The degree of pathogenicity; a measure of the severity of a disease

Question 36

Name the sites where pathogens enter the body

Answer 36

Skin, mucous membranes, placenta, parenteral route

Question 37

Pathogens use ___________ best suited to their mechanisms of _______________

Answer 37

Portals of entry; pathogenesis

Question 38

Describe how skin is a portal of entry

Answer 38

Outer layer of dead skin cells act as a barrier to pathogens; some pathogens can enter through openings or cuts

Question 39

Describe how mucous membranes are a portal of entry

Answer 39

They line the body cavities that are open to the environment; provide a moist, warm environment hospitable to pathogens

Question 40

That is the most common portal

Answer 40

Respiratory tract

Question 41

Describe how the placenta is a portal of entry

Answer 41

It typically forms an effective barrier to pathogens; pathogens may cross the placenta and infect the fetus

Question 42

Describe how the parenteral route is a portal of entry

Answer 42

Means by which the normal protection can be circumvented; pathogens are deposited directly to tissues beneath the skin mucous membranes

Question 43

Adhesion (in infection)

Answer 43

The process by which microorganisms attach themselves to cells; it is required to successfully establish colonies within the host

Question 44

Explain the process of adhesion

Answer 44

Viral or bacterial ligands bind host cell receptors; interaction can determine host cell specificity; changing/blocking a ligand or its receptor can prevent infection; inability to make attachment proteins or adhesins renders microorganisms avirulent

Question 45

Some bacterial pathogens can attach to each other to form a ___________

Answer 45

Biofilm

Question 46

Virulence factors

Answer 46

Factors that allow the pathogen to cause disease; contribute to virulence

Question 47

Name some examples of virulence factors

Answer 47

Adhesins, biofilms, extracellular enzymes, toxins, antiphagocytic factors, toxins

Question 48

Pathogenicity islands

Answer 48

Where virulence genes occur within the microorganism's genome

Question 49

Exotoxins

Answer 49

Proteins secrted by pathogens to kill host cells. Effects include fever, diarrhea, shock, and nervous system damage

Question 50

What do cytotoxins affect

Answer 50

Cells

Question 51

What do neurotoxins affect

Answer 51

Nerve cells

Question 52

What do endotoxins affect

Answer 52

Gastrointestinal tract

Question 53

Endotoxins

Answer 53

Components of gram negative outer membrane, released when they lyse. Effects include fever, chills, weakness, shock, death

Question 54

What are examples of portals of exit

Answer 54

Ear, broken skin, skin, anus, eyes, seminal vesicles, urethra, vagina, nose