Chapter 14 Flashcards

(82 cards)

1
Q

pathology - also etiology & pathogenesis

A

scientific study of disease, including etiology (cause), pathogenesis (way a disease develops) and the structural and functional changes and their effects on the body caused by the disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

etiology

A

the cause of a disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

pathogenesis

A

the way a disease develops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

pathogen

A

disease-causing microorganism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

infection

A

invasion and growth of pathogens in the body causing signs of illness, inflammation, and tissue damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

colonization

A

the presence and growth of microorganisms WITHOUT signs or symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

disease

A

abnormal state in which body is not performing its normal functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

normal microbiota/flora & locations

A

microorganisms that reside permanently in or on the body but do not cause disease under normal conditions.

LOCATIONS include skin, eyes, nose/throat, mouth, large intestine, urinary and reproductive systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Normal microbiota: Skin

sweat & oil glands
keratin
moisture content

A

Most microbes don’t become residents because secretions from sweat & oil glands have antimicrobial properties.

Keratin is also a resistant barrier, and low pH of skin inhibits many microbes.

Also, skin has a relatively low moisture content.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Normal microbiota: Eyes

conjunctiva
tears/blinking

A

Conjunctiva is the continuation of the skin or mucous membrane, contains the same microbiota found on skin.

Tears and blinking eliminate some microbes or inhibit others from colonizing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Normal microbiota: Nose/throat

microbial antagonism
nasal secretion
mucus/ciliary action

A

Although some normal microbiota are potential pathogens, their ability to cause disease is reduced by microbial antagonism.

Nasal secretions kill or inhibit many microbes, and mucus and ciliary action remove many microbes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Normal microbiota: Mouth

Moisture, warmth, presence of food
biting, chewing, tongue movements, salivary flow
saliva

A

Moisture, warmth, and constant presence of food make the mouth an ideal environment that supports very large and diverse microbial populations on the tongue, cheeks, teeth and gums.

Biting, chewing, tongue movements, and salivary flow dislodge microbes.

Saliva contains several antimicrobial substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Normal microbiota: Large intestine

largest
mucus/shedding
mucosa
diarrhea

A

contains largest # of resident microbiota in the body b/c of available moisture and nutrients.

Mucus & periodic shedding of the lining prevent many microbes from attaching to the lining of the gastrointestinal tract, and mucosa produces several antimicrobial chemicals.

Diarrhea also flushes out some of the normal microbiota.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Normal microbiota: Urinary and Reproductive systems

urethra
vag
mucus/shedding
cilia/mucus

A

Lower urethra in both sexes has resident population.

Vag has its acid-tolerant population of microbes b/c of the nature of its secretions.

Mucus and periodic shedding of the lining prevent microbes from attaching to the lining; urine flow mechanically removes microbes, and pH of urin and urea are antimicrobial.

Cilia and mucus expel microbes from cervix into the vag, and acidity of the vag inhibits or kills microbes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

transient microbiota

A

microorganisms that are present in or on the body for a period of time and then disappear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

microbial antagonism/competitive exclusion

CCSS

A

by competing for resources and/or producing bacteriocins, the normal microbiota protect the host by preventing the colonization and overgrowth of harmful microorganisms.

Includes Candida albicans, Salmonella, Shigella, Clostridium difficile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Microbial antagonism: Candida albicans

A

normal bacterial microbiota of the human vag is ~pH=4.

Presence of the normal bacterial microbiota inhibits growth of Candida albicans, which grows when balance between normal microbiota and pathogens is upset, and when pH is altered.

If population is eliminated by antibiotics, excessive douching, or deodorants, pH of vag reverts to neutral and C. albicans can flourish and become dominant microorganism there, which leads to vaginitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Microbial antagonism: E. coli

A

Produces bacteriocins (inhibits growth of other bacteria of same or related species such as pathogenic Salmonella and Shigella).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Microbial antagonism: Clostridium difficile

A

Normal microbiota of the large intestine effectively inhibit C. difficile, but if normal microbiota is eliminated (antibiotics), C. difficile can be a problem.

This microbe is responsible for nearly all gastrointestinal infections that follow antibiotic therapy, from mild diarrhea to sever or even fatal colitis (inflammation of colon).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Symbiosis

A

relationship between 2 organisms in which at least 1 organism is dependent on the other, such as the normal microbiota and the host.

Includes commensalism, mutualism, parasitism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Symbiosis: commensalism

A

one of the organisms BENEFITS, the other is unaffected.

EX: S. epidermidis on the surface of the skin (only bacteria benefits)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Symbiosis: mutualism

A

both organisms BENEFIT.

EX: E. coli in the large intestine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Symbiosis: parasitism

A

one organism benefits at the expense of the other (many disease causing bacterias)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Opportunistic pathogens

A

Do not cause disease in their normal habitat in a healthy person; may cause disease IF it gains access to other sites of the body, IF the host is weakened, IF they are present in large #s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
List Koch's postulates
Demonstrate a specific pathogenic microorganism is the cause of a specific disease. 1. pathogen must be present in every case of the disease. 2. pathogen must be isolated from the disease host and grown in pure culture. 3. the cultured pathogen must cause the disease when inoculated into a healthy, susceptible host. 4. same pathogen must be isolated from the inoculated host.
26
symptom
changes in body function; not apparent to an observer
27
signs
objective changes the physical can observe and measure
28
syndrome
specific group of symptoms and signs accompany a particular disease
29
communicable disease
disease that spreads from one host to another, directly or indirectly
30
contagious diseases
disease that easily spreads from one person to another.
31
noncommunicable disease ex
disease that does not spread from one host to another: it is caused by one's own microbiota (pnemonias), or when external microorganisms are introduced into the body (Clostridium tetani)
32
incidence # common probability
1. number of NEW cases of a disease in a population during a particular time period; 2. indicates how common a disease occurs during the time period; 3. indicator of a person's probability of developing the disease during the time period
33
prevalence proportion impact of disease on a population probability of having the disease
1. the TOTAL number of cases of a disease in a population at a specific time (either time point or time period); 2. represents the proportion of population with the disease; 3. useful for assessing the impact of a disease on a population and a person's probability of having a disease.
34
sporadic disease
occurs occasionally; ex: typhoid fever in the US
35
endemic disease
constantly present in a population; ex: common cold
36
epidemic disease
many people in a given area get it in a relatively short period of time; ex: influenza
37
pandemic disease
epidemic disease that occurs worldwide
38
acute disease
develops rapidly but does not last
39
chronic disease
develops slowly and may last or recur for a long time
40
subacute disease
intermediate between acute and chronic diseases
41
latent disease
disease that the pathogen remains inactive for a period of time before becoming active
42
herd immunity
when the majority of a population have immunity against an infectious disease, the chance of the nonimmunized individuals to contract the disease is little: "community immunity"
43
local infection
invading microorganism are limited to a small area of the body
44
systemic infection
microorganism or their products are spread throughout the body by the blood or lymph
45
focal infection
infection originated from a local infection, later the pathogen or its products spread from local infection area to the other parts of the body
46
sepsis
toxic inflammatory condition arising from the spread of microbes
47
septicemia
blood poisoning, systemic infection arising from multiplication of pathogens in the blood; common example of sepsis.
48
bacteremia
presence of bacteria in the blood
49
toxemia
presence of toxins in the blood
50
viremia
presence of viruses in the blood
51
primary infection
acute infection that causes the initial illness
52
secondary infection
caused by opportunistic pathogen after primary infection has weakened the body's defenses
53
subclinical (inapparent) infection
inapparent infection; does not cause any noticible disease
54
5 sequential stages of infectious diseases
IPIDC --> ``` incubation period, predromal period, period of illness, period of decline, period of convalescence. ``` Patient can be infectious during every stage; infections can be spread even during incubation and convalescence.
55
incubation period
interval btw initial infection and first appearance of signs or symptoms
56
prodromal period
short period following the incubation period in some diseases; not all diseases have it; early, mild symptoms of disease, such as aches and malaise
57
period of illness
most severe stage; apparent signs and symptoms of disease; usually when a patient goes to a physician; immune system has not fully responded to pathogens; WBCs may increase/decreases; treatments and patient's defense end of the period of illness, or patient dies during this period
58
period of decline
signs and symptoms subside; immune response and products of imune response peak in this stage
59
period of convalescence
tissues repaired; patient regains strength and recovers
60
reservoir of infection
sites, living or nonliving, where pathogens are maintained as a continual source of illness. 3 types: Human, animal and nonliving
61
Human reservoir
HUMAN: people with signs and symptoms or carriers (show no sign of illness);
62
Animal reservoir
ANIMAL: zoonoses are diseases transmitted from animals to humans;
63
Nonliving reservoir
NONLIVING: soil, water, foods
64
3 principle routes of disease transmission; examples
contact, vehicle, vector
65
direct contact transmission; examples
person-to-person physical contact; touching, kissing, sex. Common diseases: cold, flu, staph infections, hep A, measles, STDs
66
indirect contact transmission; examples
mediated through a nonliving object called a fomite. Examples: tissues, handkerchiefs, towels, bedding, diapers, drinking cups, eating utensils, toys, money, thermometers. AIDS, hep B, tetanus
67
droplet transmission; examples
Microbes in droplet nuclei (mucus droplets) discharged through coughing, sneezing, talking, etc. Travels <1 meter. Examples: cold, flu, pneumonia, pertussis (whooping cough)
68
waterborne; examples
spread by water contaminated with untreated/poorly treated sewage. EX: cholera
69
foodborne; examples
transmitted in foods incompletely cooked, poorly refrigerated, or prepared under unsanitary conditions. EX: food poisoning, tapeworm manifestation
70
airborne; examples
spread of agents of infection by droplet nuclei in dust that travel > 1 meter from reservoir to host. EX: measles, tuberculosis
71
vector transmission; examples
animals that transmit diseases from one host to another. - mechanical or biological transmission
72
mechanical transmission; examples
passively carries the pathogens such as on insect's feet or other body parts. Generally not a host for the multiplication of the pathogen (vs biological transmission) EX: housefly can transfer pathogens of typhoid fever and bacillary dysentery (shigellosis) from feces of infected people to food
73
biological transmission; examples
transmit pathogens and serves as host for the multiplication of pathogens. EX: arthropod bites infected person or animal and ingests infected blood. Pathogen reproduces in vector, increasing the number of pathogens which increases possibility that it will be transmitted to another host.
74
nosomial infection
infection acquired in hospital, nursing home, health care facilities. Does not show any evidence of being present or incubating at the time of admission to a hospital; it is acquired as a result of the hospital stay. Important to wash your hands. Nosocomial infections generally result from: microorgs in the hospital environment, compromised/weakened status of host, and chain of transmission in the hospital.
75
emerging infectious disease
new or changing, showing an increase in incidence recently or potentially in the near future. 75% of EIDs are zoonotic, viral, and vector-borne
76
epidemiology 3 investigators SSN 3 types of investigation DAE
study of when and where diseases occur and how they are transmitted in populations. 3 investigators: John Snow, Ignas Semmelweis, Florence Nightingale. 3 types of investigation: descriptive, analytical, experimental
77
descriptive epidemiology
collect all data that describe occurrence of the disease
78
analytical epidemiology
analyze a particular disease to determine its probable cause, mode of transmission, and possible means of prevention
79
experimental epidemiology
test a hypothesis concerning the cause of a disease
80
morbidity
incidence of specific notifiable diseases
81
mortality
number of deaths from these diseases
82
notifiable infectious disease
diseases for which physicians are required by law to report cases to the US public health svc