Lecture 13 Flashcards
1
Q
A condition in which pathogenic microorganisms penetrate host defenses, enter the tissues, and multiply
A
infection
2
Q
- Cumulative effects of infection damage
- Disruption of tissues and organs
- Results in disease
A
pathologic state
3
Q
Any deviation from health
A
disease
4
Q
factors that cause disease
A
infections, diet, genetics, aging
5
Q
Disruption of tissues or organs caused by microbes or their products
A
infectious disease
6
Q
Large and diverse collection of microbes living on and in the body
A
normal biota
7
Q
known as resident or indigenous biota
A
normal flora
8
Q
- Include an array of bacteria, fungi, protozoa and viruses
- These organisms have a profound effect on human biology
A
normal biota
9
Q
sites that harbor a known normal biota
A
- skin
- respiratory tract and lungs
- GI tract
- urethra
- genitalia
- ear canal
- eye
10
Q
sterile sites of human body
A
11
Q
- Influence the development of organs
- Prevent the overgrowth of harmful microorganisms
A
benefits of normal biota
12
Q
- The general antagonistic effect “good” microbes have against intruder microorganisms
- Microbes in a steady, established relationship are unlikely to be displaced by incoming microbes
A
microbial antagonism
13
Q
can influence many facets of your overall health.
A
intestinal biota
14
Q
Differences in the gut microbiome have been preliminarily associated with differences in the risk for:
A
Heart disease Asthma Autism Rheumatoid arthritis Even thoughts, moods, and propensity for mental illness
15
Q
factors that weaken host defenses and increase susceptibility to infection
A
- age
- AIDS/genetic defects
- surgery
cancer, liver malfunction, diabetes - chemotherapy
- physical and mental stress
- other infections
16
Q
- Caused by biota already in the body
- Can occur when normal biota is introduced to a site that was previously sterile
A
endogenous infections
17
Q
example of endogenous infections
A
Escherichia coli entering the bladder, resulting in a UTI
18
Q
A growing number of doctors and scientists believe fetuses are seeded with normal microbiota
A
in utero
19
Q
table 13.4
A
20
Q
- A microbe whose relationship with its host is parasitic
- Results in infection and disease
- Type and severity of infection depend on both the pathogenicity of the organism and the condition of the host
A
pathogen
21
Q
Describes an organism’s potential to cause infection or disease
A
pathogenicity
22
Q
Capable of causing disease in healthy persons with normal immune defenses
A
true pathogens
23
Q
Cause disease when:
- The host’s defenses are compromised
- When they become established in a part of the body that is not natural to them
A
opportunistic pathogens
24
Q
The relative severity of the disease caused by a particular microorganism
A
virulence
25
Any characteristic or structure of the microbe that contributes to toxin production or induction of an injurious host response
virulence factors
26
steps to infection
1. entry
2. attach to the host
3. surviving host defenses
4. disease
27
A characteristic route taken by a microbe to initiate infection
Usually through skin or mucous membranes
portal of entry
28
originating outside the body
exogenous
29
already existing in the body
endogenous
30
sites of entry in skin
nicks
abrasions
punctures
conjunctiva
31
The Gastrointestinal Tract as Portal
food, drink, or other ingested substances (adapted to survive digestive enzymes and abrupt pH changes)
32
gateways to the respiratory tract
oral cavity
| nasal cavity
33
Pathogens transmitted by sexual means
Account for 4% of infections worldwide
13 million new cases in the U.S. each year
STI's
34
- Formed by maternal and fetal tissues
- Separates the blood of the developing fetus from that of the mother
- Permits diffusion of dissolved nutrients and gases to the fetus
placenta
35
how are pathogens infected during pregnancy and birth
- cross the placenta and are spread by the umbilical vein into the fetal tissues.
- are transmitted perinatally as the child passes through the birth canal.
36
common infections of the fetus and neonate.
TORCH
37
TORCH
```
Toxoplasmosis
Other diseases: syphilis, coxsackievirus, varicella-zoster virus, AIDS, chlamydia
Rubella
Cytomegalovirus
Herpes simplex virus
```
38
a minimum number of microbes required for an infection to proceed
infectious dose
39
White blood cells that engulf and destroy pathogens by means of enzymes and antimicrobial chemicals
phagocytes
40
Virulence factor used by pathogens to avoid phagocytes
| Circumvent some part of the phagocytic process
antiphagocytic factors
41
- Structures, products, or capabilities that allow a pathogen to cause infection in the host
- Adaptations that a microbe uses to invade and establish itself in a host
- Determine the degree of tissue damage that occurs
virulence factors
42
table 13.8
--
43
patterns of infection
- finding a portal of entry
- attaching
- surviving host defenses
- causing damage
- exiting host
44
Microbe enters the body and remains confined to a specific tissue
(boils, fungal skin infections, warts)
localized infection
45
When an infection spreads to several sites and tissue fluids, usually in the bloodstream.
systemic infection
46
measles, rubella, chickenpox, AIDS
viral
47
: brucellosis, anthrax, typhoid fever, syphilis
bacterial
48
histoplasmosis, cryptococcosis
fungal
49
Exists when the infectious agent breaks loose from a local infection and is carried to other tissues
focal infection
50
examples of focal infection
- Tuberculosis
- Streptococcal pharyngitis: scarlet fever
- Toxemia:
51
infection remains localized, toxins are carried through the blood to the target tissue
toxemia
52
- Several agents establish themselves simultaneously at the infection site
- In synergistic infections, microbes cooperate in breaking down tissue
- In other mixed infections, one microbe creates an environment that enables another microbe to invade
mixed infection
53
gas gangrene, wound infections, dental caries, human bite infections
polymicrobial disease
54
initial infection
primary infection
55
occurs when a primary infection is complicated by another infection caused by a different microbe
secondary infection
56
come on rapidly
| have short-lived effects
acute infections
57
progress and persist over a long period of time
chronic infections
58
Any objective evidence of disease as noted by an observer
sign
59
Subjective evidence of disease as sensed by the patient
symptom
60
A disease identified or defined by a certain complex of signs and symptoms
a disease identified or by a certain complex of signs and symptoms
61
table 13.9
----
62
Earliest symptom of disease
inflammation
63
accumulation of fluid in afflicted tissue
edema
64
Walled-off collections of inflammatory cells and microbes in the tissues
granulomas and abscesses
65
swollen lymph nodes
lymphadenitis
66
inc in WBC
leukocytosis
67
dec in WBC
leukopenia
68
General state in which microbes are multiplying in the blood and are present in large numbers
septicemia
69
Small numbers of bacteria are present in the blood but not multiplying
small numbers of bacteria are present in the blood but not multiplying
70
Presence of viruses in the blood, whether or not they are actively multiplying
viremia
71
- Host is infected but does not manifest the disease
- Patient experiences no symptoms or disease and does not seek medical attention
- Most infections are attended by some sort of sign
Asymptomatic, subclinical, or inapparent infections:
72
portal of exit
Secretion
Excretion
Discharge
Sloughed tissue
73
- A dormant state of an infectious agent
| - During this state, a microbe can periodically become active and produce recurrent disease
latency
74
Long-term or permanent damage to organs and tissues
sequelae
75
The time from initial contact with the infectious agent to the appearance of first symptoms
incubation period
76
When the earliest notable symptoms of infection appear
prodromal period
77
Infectious agent multiplies at high levels and exhibits greatest virulence
period of invasion
78
Patient responds to infection and symptoms decline
convalescent stage
79
A permanent place for an infectious agent to reside
reservoir
80
distinct from a reservoir
source
81
An individual who inconspicuously shelters a pathogen and can spread it to others without knowing
carrier
82
living reservoirs table
--
83
a live animal that transmits an infectious agent from one host to another
vector
84
majority of vectors are
arthropods
85
- Actively participates in a pathogen’s life cycle
| - Serves as a site in which it can multiply or complete its life cycle
biological vector
86
- Not necessary to the life cycle of an infectious agent
| - Merely transport it without being infected
mechanical vectors
87
table 13.10
---
88
Essential aim of the study of infection and disease is determining the etiologic agent (causative agent).
koch's postulates to determine etiology
89
Developed a standard for determining causation of disease that stood the test of scientific scrutiny
Determined the causative agent of anthrax
robert koch
90
a series of proofs that established the principal criteria for etiologic studies
koch's postulates
91
given off by live cells, have highly specific targets and physiological effects
exotoxins
92
given off when the cell wall of gram - bacteria disintegrates has more generalized physiological effects (fever, malaise, aches, shock)
endotoxins
93
mechanisms of adhesion by pathogens
- fimbrae
- capsules
- spikes
94
three ways microbes damage the host
- exoenzymes
- toxins
- blocked phagocytic response
95
results in complete lysis of red blood cells incorporated in agar, leaving area of complete clearing around the bacterial colony
beta hemolysis
96
incompletely hemolysis the RBC, leading to a green tint where the exotoxin has acted
alpha hemolysis
97
infected but shown symptoms of disease
asymptomatic and incubating carriers
98
recuperating patients without symptoms, continue to shed viable microbes and convey the infection to others
convalescent carriers
99
individuals who shelter the infectious agent for a long period after recovery because of the latency of the infectious agent
chronic carrier
100
medical and dental personnel who must constantly handle patient material that are heavily contaminated
passive carriers
