PATHOGENESIS Flashcards
(the ability to cause disease)
pathogenicity
the steps or mechanisms involved in the development of a disease).
pathogenesis
colonization by a pathogen
when a pathogen lands on or enters a person’s body and
establishes residence there
infection
4 phases in the course of an infectious disease
incubation period
prodromal period
period of illness
convalescent period
the time that elapses between
arrival of the pathogen and
the onset of symptoms
The incubation period
time during which the
patient feels “out of sorts” but is not yet experiencing
actual symptoms of the disease
The prodromal period
the time during which the
patient experiences the typical symptoms associated
with that particular disease (e.g., sore throat,
headache, sinus congestion)
The period of illness
the time during which the
patient recovers.
The convalescent period
3 types of disease (length)
chronic disease
subacute diseases.
acute diseases
a disease that has an insidious (slow) onset and lasts a long time; e
chronic disease
tuberculosis, leprosy (Hansen disease), and syphilis is what type of disease
chronic disease
a disease having a sudden
onset can develop into a long-lasting disease; come on more suddenly than a chronic disease, but less suddenly than an acute disease
subacute diseases.
some evidence of
a disease that is experienced
or perceived by the patient;
something that is subjective.
symptom of a disease
clinical disease; is a
disease in which the patient is experiencing symptoms.
symptomatic disease
subclinical disease; is a
disease that the patient is unaware of because he or she is not experiencing any symptoms
asymptomatic disease
is defined as some type of objective evidence of a disease
sign of a disease
is a disease that is lying
dormant, not currently
manifesting itself.
latent infections
Herpes virus infections, such as cold sores (fever blisters), genital herpes infections, and shingles are what type of infections
latent infections
steps in the pathogenesis of infectious disease
Entry
Attachment
Multiplication
Invasion
Evasion
Damage
(the cause of scarlet fever
erythrogenic toxin
The physical attributes or properties of pathogens that enable them to escape various host defense mechanisms and cause disease are called
virulence
factors
used to describe the molecule on the surface of pathogen that is able to recognize and bind to a particular
receptor
adhesin
and ligand
used to describe the
molecule on the surface of a
host cell that a particular
pathogen is able to recognize
and attach to
receptor and
integrin
pathogens that must live within host cells to survive and multiply; they are referred to as
obligate intracellular pathogen
are long, thin, hairlike, flexible
projections composed primarily of an array of proteins called pilin
Bacterial fimbriae
are capable of
both an intracellular and extracellular existence
Facultative Intracellular Pathogens
virulence factors examples
fimbriae
capsules
flagella
Exoenzymes
Coagulase
Hyaluronidase
Collagenase
examples of exoenzymes
Lecithinase
Kinases
they serve an antiphagocytic
function they protect encapsulated bacteria from being phagocytized by phagocytic white blood cells
Capsules
enable (motile)
bacteria to invade aqueous
areas of the body that nonflagellated (nonmotile) bacteria are unable to reach
Flagella
pathogens release these enzymes that enable them to evade host defense mechanisms, invade, or cause damage to body tissues.
exoenzymes
this factor
- binds to prothrombin, forming a complex called
staphylothrombin - clot plasma and thereby to form a sticky coat
of fibrin around themselves for protection
Coagulase
enzymes that
lyse (dissolve) clots; therefore, pathogens that produce
kinases are able to escape from clots
Kinase
enables pathogens to spread
through connective tissue by
breaking down hyaluronic acid
Hyaluronidase
are enzymes that
cause damage to the host’s red blood cells
Hemolysins
Substances that cause fever are known as
pyrogens.
a life-threatening condition resulting from
very low blood pressure and an inadequate blood supply
shock
what toxin is a component of the cell walls of gram-negative bacteria
Endotoxin
are toxins that affect the gastrointestinal tract, often causing diarrhea and
sometimes vomiting
enterotoxins
pathogens are
able to periodically change their surface antigens, a
phenomenon known as
antigenic variation
- Which of the following virulence factors enable(s)
bacteria to attach to tissues?
a. capsules
b. endotoxin
c. flagella
d. pili
d
Neurotoxins are produced by:
a. Clostridium botulinum and Clostridium tetani.
b. Clostridium difficile and Clostridium perfringens.
c. Pseudomonas aeruginosa and Mycobacterium tuberculosis.
d. Staphylococcus aureus and Streptococcus pyogenes.
a
. Which of the following pathogens produce enterotoxins?
a. Bacillus cereus and certain serotypes of Escherichia
coli
b. C. difficile and C. perfringens
c. Salmonella spp. and Shigella spp
d
A bloodstream infection with __________ could result in the release of endotoxin into the bloodstream.
a. C. difficile or C. perfringens
b. Neisseria gonorrhoeae or E. coli
c. S. aureus or M. tuberculosis
d. S. aureus or S. pyogenes
b
Communicable diseases are most easily transmitted
during the:
a. incubation period.
b. period of convalescence.
c. period of illness.
d. period
c
Enterotoxins affect cells in the:
a. central nervous system.
b. gastrointestinal tract.
c. genitourinary tract.
d. respiratory tract.
b
. Which of the following bacteria is least likely to be
the cause of septic shock?
a. E. coli
b. Haemophilus influenzae
c. Mycoplasma pneumoniae
d. Neisseria meningitidis
c
Which of the following produces both a cytotoxin
and an enterotoxin?
a. C. botulinum
b. C. difficile
c. C. tetani
d. Corynebacterium diphtheriae
b
Which of the following virulence factors enable(s)
bacteria to avoid phagocytosis by white blood cells?
a. capsule
b. cell membrane
c. cell wall
d. pili
a
. Which of the following can cause toxic shock
syndrome?
a. C. difficile and C. perfringens
b. M. pneumoniae and M. tuberculosis
c. N. gonorrhoeae and E. coli
d. S. aureus and S. pyogenes
d
