Chain of Infection, Risk Factors, Immune System, Immunocompromised Host Flashcards
(160 cards)
1
Q
Immune response that does not involve antibodies but rather involves the activation of macrophages and NK cells, the production of antigen specific cytotoxic t lymphocytes, and the release of various cytokines in the response to an antigen
A
Cell Mediated Immunity
2
Q
An aspect of specific immune responses directed at particular antigens it takes the form of unique antibodies produced by B lymphocytes that have been specifically selected to neutralize the antigen at hand.
A
Humoral Immune response
3
Q
Types of T cells
A
Cytotoxic t cells- CD8
Helper T-cells- CD4
4
Q
Types of B cells
A
Plasma and memory cells
5
Q
Substances such as interferon, interleukin, and growth factors which are secreted by certain cells of the immune system and have an effect on other cells
A
Cytokines
6
Q
Where are secretory antibodies present in the body?
A
Oral secretions, tears, intestinal contents, breast milk, prostate, and the female reproductive system
7
Q
Glycoprotein molecules produced by the plasma cells that recognize and bind to antigens and aid in their destruction
A
immunoglobulins
8
Q
Late occurring in a meeting response and longest lived because it enters interstitial tissue relatively easily it is the major antibody to protect tissue
A
IgG
9
Q
First reacting immunoglobulin and an adaptive immune response to an infection and is generally produced for no more than 6 months after the onset of infection
A
IgM
10
Q
Principal’s secretory antibody and humans primarily produced in plasma cells residing in mucous membranes. Effective in preventing viral infections of respiratory tract and intestinal mucosa
A
IgA
11
Q
Present principally on the surface of lymphocytes and it serves to bind specific antigens. Functions in later immune responses
A
IgD
12
Q
Principal allergy inducing immunoglobulin known as reagin
A
IgE
13
Q
Portals of entry for opportunistic pathogens
A
Skin
Lungs
Oropharynx
GI tract of neutropenic host
14
Q
What illnesses are there passive IM or IV immunoglobulin available for?
A
Hepatitis A
Hepatitis B
Tetanus
Rabies
Varicella
15
Q
IVIG is not generally recommended for the following patients…
A
Routine oncology patients
16
Q
Rarely appropriate but may be used in very select patients (chemo or bone marrow transplants with bacterial or fungal infection that doesn’t respond to antimicrobials
A
Granulocyte transfusions
17
Q
Secreted glycoproteins that bind to receptor proteins on the surfaces of hematopetic stem cells thereby activating intracellular signaling pathways that can cause the cells to proliferate and differentiate into white blood cells
A
Colony stimulating factors
18
Q
When would colony stimulating factors be used?
A
Chemo patients with neutropenia
19
Q
Chain of transmission
A
- Infectious agent
- Reservoir
- Portal of exit
- Mode of transmission
- Portal of entry
- Susceptible host
20
Q
Virulence
A
Ability to grow and multiply
21
Q
Infectivity
A
Ability to enter tissue
22
Q
Pathogenicity
A
Ability to cause disease
23
Q
Duration of exposure
A
Length of time person exposed to organism
24
Q
Size of innoculm
A
Number of organisms needed to cause disease
25
High risk procedures for HAIs
1. IV access and central lines
2. Mechanical ventilation
3. Indwelling urinary catheters
4. Hemodialysis
5. Parenteral nutrition
26
Infection versus colonization
Colonization, shows on culture but no signs or symptoms
Infection - tissue damage and disease, signs and symptoms
27
Toxin that is mostly Gram + organisms, proteins that are secreted from the cell
Exotoxin
28
Toxin that is highly antigenic and has vax
Exotoxin
29
Toxin that has high toxicity
Exotoxin
30
Toxin that is heat liable
Exotoxin
31
Toxin that is mostly gram negative
endotoxin
32
Toxin from LPS, released when bacterial cell is killed
endotoxin
33
toxin that is not highly antigenic
endotoxin
34
toxin that is heat stable
Endotoxin
35
toxin that has low toxicity
Endotoxin
36
Examples of the exotoxin
cholera
Tetanus
Botulism
37
Examples of endotoxins
Meningococcemia
Sepsis
38
1. Ability to Survive in env between hosts
2. Mechanism for transmission to new host
3. Ability to attach to a new host, invade, and disseminate
Factors for virulence
39
Endogenous opportunistic organism in lungs
Mycobacterium tuberculosis
Coccidioides immitis
Histoplasma
Pneumocystis jirovechii
40
Endogenous opportunistic organisms in skin
Coagulase negative staph
Corynebacteria
Maleassezia furfur
HSV and herpes zoster
41
Endogenous opportunistic organisms in GI tract
Enterococcus
Streptococcus bovis
Clostridium septicum
Candida spp
Bacterioides fragilis
42
Endogenous opportunistic organism in oropharynx
Candida spp
43
Endogenous opportunistic organism in central nervous system
Toxoplasma gondi
44
Exoogenous opportunistic organism on hands/ fomites
Clostridium difficile
Viruses other than herpes
45
Exogenous opportunistic organisms in water
Legionella
Cryptosporidium
46
Exogenous opportunistic organism in environment
Zygomycetes (fungi in rotten wood that cause rare pulmonary disease)
Rapidly growing mycobacteria (fortuitum chealonae)
47
Exogenous opportunistic organism in ventilation during construction
Aspergillus
48
Opportunists that can be either endogenous or exogenous
1. Aerobic gram negative bacilli (endogenous from oropharynx and gi tract, exogenous from contaminated food or fomites)
2. Staph aureus
Endogenous on skin and in nasal carriage, exogenous from personnell hands
49
What medical interventions increase risk?
1. Presence of invasive devices
2. Placement in an ICU
3. Exposure to antibiotics or certain medications
4. Immunosuppressive therapy
5. Length of hospitalization
6. Staffing ratios
7. Experience in training of care provider for certain device- associated infections
9. Increase number of hcp examinations / procedures
50
Name 3 examples of patient factors that increase risk of transmission
- Immunosuppressive diseases and disorders
- malignant disorders
- patient Apache score
- poor nutritional status
- age
- diabetes
- pregnancy
- travel history
- occupation
- residence
- contact with certain pets of animals
- extensive burn wounds
- trauma
51
What bacteria typically cause bacterial meningitis?
Streptococcus pneumoniae
Neisseria meningitidis
Haemophilus influenzae
Streptococcus agalactiae
Listeria monocytogenes
52
What bacteria typically cause otitis media?
Streptococcus pneumoniae
53
What bacteria typically cause community acquired pneumonia?
Streptococcus pneumoniae
Haemophilus influenzae
Staphylococcus aureus
54
What types of bacteria typically cause atypical pneumonia?
Mycoplasma pneumoniae
Chlamydia pneumoniae
Legionella neumophilia
55
What bacteria causes tuberculosis pneumonia?
Mycobacterium tuberculosis
56
What type of bacteria typically cause skin infections?
Staphylococcus aureus
Streptococcus pyogenes
Pseudomonas aeruginosa
57
What type of bacteria typically cause sexually transmitted diseases?
Chlamydia trachomatis
Neisseria gonorrheae
Treponema pallidum
Ureaplasma urealyticum
Haemophilus ducreyi
58
What type of bacterial infections typically cause eye infections?
Staphylococcus aureus
Neisseria gonorrhea
Chlamydia trachomatis
59
What type of bacterial infections typically cause sinusitis?
Streptococcus pneumoniae
Haemophilus influenzae
60
What bacterial infections typically cause upper respiratory tract infections
Streptococcus pyogenes
Haemophilus influenzae
61
What type of bacterial infections typically cause gastritis
Helicobacter pylori
62
What type of bacteria typically cause food poisoning?
Campylobacter jejuni
Salmonella
Shigella
Clostridium
Staphylococcus aureus
E coli
63
What type of bacterial infections usually cause UTIs
E coli
Other enterobacteriaceae
Staphylococcus saprophyticus
Pseudomonas aeruginosa
64
Examples of communicable diseases when hcp should be restricted?
Diarrhea
Group a strep
Conjunctivitis
Draining dermatitis
Exudative lesions
Active tuberculosis
Infectious rashes
65
What are some personnel practices that are important for infection prevention?
1. Immunization
2. Restriction of hcp with a communicable disease
3. Assignment of patients to be careful by immune HCPs
4. Protocol for evaluation and follow-up of employee exposure to infectious diseases
66
How long can staphylococcus aureus including MRSA survive in the environment?
7 days to over 12 months
67
How long can C diff survive in the environment?
Over 5 months
68
How long can norovirus survive in the environment?
8 hours to over 2 weeks
69
Immune compromised patients include only...
1. Neutropenia (neutrophil count < 500
2. Leukemia, lymphoma, or HIV positive with a CD4 count <200
3. Splenectomy
4. History of solid organ or hematopetic stem cell transplant
5. Cytotoxic chemotherapy
5. On enteral or parenteral steroids daily for >14 days
70
Describe management of the immunocompromised host
1. Recognize host effects that are associated with impaired resistance
2. Knowledge of the type of infection to anticipate in each category of immune compromise
3. Most common portals of entry for opportunistic organisms
4. Fact that clinical manifestations of illness may be different in the immunocompromised host
5. Understanding of the broad array of modality for infection prevention
71
How do clinical manifestations differ for neutropenic patients
They have little perulance at the site of infection and less obvious chest radiographic findings
72
How do clinical manifestations differ for patients receiving corticosteroids
Diminished or absent fever response
73
What are the two most common pathogens for burn victims?
Staphylococcus aureus
Pseudomonas aeruginosa
74
What are the reasons that nasotracheal or orotracheal intubation can contribute to healthcare associated pneumonia?
- Blockage of sinus drainage
- Mechanical trauma to mucosa
- Impaired swallowing of secretions
- Adherence of bacteria to foreign body
- Pulling of secretions around the cuff
- Mucosal ischemia around the cuff
- Impaired ciliary clearance and cough
75
In___ patients, the gastrointestinal tract is often the most important source for bacteremia
Neutropenic
76
How long is someone with a recent bone marrow transplant considered immunocompromised?
6 months
77
List of common opportunistic bacterial infections associated with cell-mediated immunity dysfunction
- Listeria monocytogenes
- Salmonella spp
- Mycobacterium spp, including M tuberculosis
- Nocardia
- legionella pneumophila
- rhodococcus equi
- pseudomonas pseudomallei
78
Most common opportunistic infections associated with breaks in cutaneous integrity
- staph aureus
- strep pyogenes
- corynebacteria (diabetics)
- maleassezia furfur (lipid IV)
79
Opportunistic infections associated with defects in mucous membranes
Anaerobic bacteria
- bacteroides fragilis
- clostridium perfringens
- c. Septicum
Aerobic bacteria
- gram - bacilli
Candida spp
Enterococcus spp
Streptococcus bovis
80
Opportunistic infections associated with obstruction of the lungs
Oral Flora
Nosocomial gram-negative
Staphylococcus aureus
81
Opportunistic infection that result from obstruction of a natural body passage in the biliary and pancreatic systems
Aerobic gram-negative bacilli
Enterococcus
Anaerobes
82
Most common opportunistic infections associated with obstruction of a natural body passage specifically the colon
Gram negative bacilli
Anaerobes
Streptococcus bovis
83
Opportunistic infections associated with granulocytopenia for 2 weeks or less
Gram negative bacilli
Staphylococcus aureus
Coagulase negative staphylococcus
84
Absolute neutrophil count of 500 ml
Granulocytopenia
85
Opportunistic infections associated with Granulocytopenia for more than 2 weeks
Gram negative bacilli
Staphylococcus aureus
Coagulase negative staphylococcus
Candida spp
T glabrata
Aspergillus spp
86
Fungal opportunistic infections associated with dysfunction of cell-mediated immunity
Cryptococcus neoformans
Candida spp
Coccidioides y
Histoplasma calsulatum
Penicillium marnwffej
Pneumocystis jirovechi
87
Opportunistic viral infections associated with cell mediated immunity dysfunction
Herpes group virus especially cytomeglovirus
Herpes zoster
88
Opportunistic protozoa associated with cell-mediated immunity dysfunction
Toxoplasma Gondii
Cryptosporidium spp
89
Opportunistic helminths associated with cell mediated immunity dysfunction
Strongyloides stercoalis
90
Opportunistic infections associated with splenectomy or humoral dysfunction
Encapsulated bacteria
- streptococcus pneumoniae
- encapsulated strains of Haemophilus influenzae
- Neisseria meningitidis
91
Describe mycobacteria cell wall
Mycolic acid (cord factor), waxy surface impervious to chemicals or dyes
92
How to break the chain: susceptible host
Immunizations
Treatment underlying disease
Health insurance
Patient education
93
Any person, especially those receiving healthcare
Susceptible host
94
Part of chain - bacteria, fungus, viruses, parasites
Infectious agent
95
How to break the chain infectious agent
Dx and treatment
Antimicrobial stewardship
96
Chain of infection- dirty surfaces and equipment, people, water, animals and insects soil
Reservoir
97
How to break the chain reservoir
Cleaning, disinfection, sterilization
Infection prevention policies
Pest control
98
Chain: open wounds, skin, splatter body fluids, aerosols
Portal of exit
99
How to break the chain portal of exit
Hand hygiene
PPE
Control of aerosols and splatter
Respiratory etiquette
Waste disposal
100
Chain: contact (direct or indirect), ingestion, inhalation
Mode of transmission
101
How to break the chain: mode of transmission
Hand hygiene
PPE
Food safety
Cleaning, disinfection, sterilization
Isolation
102
Chain: broken skin, incisions, resp tract, mucous membranes, catheters and tubes
Portal of entry
103
How to break the chain portal of entry
Hand hygiene
PPE
Personal hygiene
First aid
Removal of catheters ans tubes
104
Presence of invasive devices
Placement in ICU
Exposure to antibiotics or certain meds
Immunosuppressive therapy
Length of hospitalization
Staffing ratio
Experience and training of hcp
Increased number of hcp examinations/ procedures
Medical interventions that increase risk
105
Immunosuppressive diseases
Malignant disorders
Apache score
Poor nutrition
Age
Diabetes
Pregnant
Travel history occupation
Residence
Contact with certain pets
Extensive burn wounds
Trauma
Patient factors that increase risk of transmission
106
How far for large droplets travel
1-3 ft
107
How far do droplet nuclei travel?
6-150+ feet
108
How far do small droplets travel?
3-6 ft
109
Personnel practices
1) immunization
2) restriction of hcp that are sick
3) Assignments to immune HCPs
4) Protocols for exposures
110
Occurs when microbes inhabit a specific body site but don't cause signs and symptoms
Colonization
111
Clinical signs of illness or inflammation due to tissue damage cause by microbe invasion
Infection
112
Measure of a microbes ability to invade and create disease in a host
Virulence
113
Initial element of virulence
Ability of an organism to survive in the external environment during Transit between hosts
114
What is the second element of virulence
Mechanism for transmission to a new host
115
Proteins produced inside pathogenic bacteria, most commonly gram-positive bacteria, as part of their growth and metabolism. They are then secreted or released into the surrounding medium following lysis
Exotoxin
116
Lipid portions of lipopolysaccharides that are part of the outer membrane of the cell wall of gram-negative bacteria. They are liberated when the bacteria die and the cell wall breaks apart
Endotoxins
117
Part of immune system that is Induced, mediated, a regulated by t lymphocytes and mononuclear phagocytes
Cell mediated immune system
118
Part of immune system that gains of the ability to recognize virus infected cells and adhere to and kill them
Antibody mediated humoral immune system
119
Cells that are part of the antibody mediated humoral immune system
CD4
Cd8 (cytotoxic or suppressive)
B cells
120
Substances that have specific structures and biological activities
Cytokines
121
True or false, patients may have more than 1 type of immunocompromise
True
122
Thorough _____ and detailed physical exam often reveal potential problems of the immunocompromised host
History taking
123
What are the most important precautions for the immunocompromised host?
Standard precautions and transmission based precautions when indicated
124
Nhsn classification of immunocompromised
Neutropenia
Leukemia
Lymphoma
HIV positive with CD4 count less than 200
Splenectomy
Solid organ transplants
Hematopoietic stem cell transplant
Cytotoxic chemotherapy
Enteral or parenteral administered steroids
125
Comprehensive management of immunocompromised host
Recognition of categories of host defects that are associated with impaired resistance
Knowledge of the type of infection to anticipate in each category of immune compromise
The most common portals of entry for opportunistic organisms
The fact that clinical manifestations of illness may be different in the immuno compromised host
And understanding of the broad array of modalities for prevention of infection
126
True or false: most patients have abnormalities that may wax or wane with time and therapy
True
127
Is determined by the interaction of several variables including host defense defects caused by the disease process, the type of immunological abnormality induced by a specific agent, the dose duration and temporal sequence of immunosuppressive therapy, the presense or absence of neutropenia and or lymphopenia, the state of humoral and cellular host defenses, the integrity of the skin and mucosal surfaces of the body, metabolic factors, abnormalities of the reticular endothelial system most notably the spleen, and the presence or absence of immunomodulating infections such as HIV hepatitis etc
Net state of immunosuppression
128
Categories of host effects associated with impaired resistance- what causes defects in the cutaneous barrier
1. Surgical incisions
2. Thermal or chemical burn
3. Traumatic injuries to the skin
4. Severe dermatologic conditions
5. Indwelling IV lines
6. Injections
7. Ulcers
129
What are some of the severe dermatological conditions that can cause defects in the cutaneous barrier?
Poorly controlled eczema or psoriasis
Scleroderma
Mycosis fungoides
Chronic fungal infections of the skin or nail beds
130
What causes mucous membrane barrier defects
1. Mucositis from chemo
2. Trauma to the head and neck
3. Smoking
4. Inhalation injuries
5. Poor oral hygiene
6. Erosions from nasogastric or endotracheal tubes or indwelling Foley catheters
7. Antacids, proton pump inhibitors, etc
131
Why do antacids and proton pump inhibitors impact the mucous membrane
They decrease the number of ingested organisms necessary to cause GI disease and they allow a reservoir for bacteria to develop in the stomach which can be regurgitated and aspirated
132
Part of immune system that is born ready, ready to immediately act
innate immune system
133
Physical barriers of immune system
Skin
mucous membranes
134
Chemical barriers of immune system
Lysozyme
Sweat
Stomach acid
135
Role of complement immune system
When triggered, chemicals punch holes in membrane
136
signs of inflammation
red
hot
swollen
Painful
137
histamine leukocytes
basophils
138
Role of basophils
Release mast
139
leukocytes that fight parasites (ie helminths)
eosinophils
140
common leukocyte that use bleach and peroxide to kill invaders
neutrophils
141
dendritic leukocytes that eat invaders and present their antigens
macrophages
142
Where are all leukocytes produced?
Bone marrow
143
This arm of the immune system is always ready to learn and remember, it requires activation and responds to specific pathogens and forms memory cells
Adaptive immune response
144
How are helper t-cells activated?
antigen presenting cells
145
What is the role of helper T cells?
create memory t cells and activate cytotoxic T cells and B cells
146
What is the role of cytotoxic t cells?
kill pathogens
147
What is the role of B cells?
Create memory B-cells and plasma B cells create antibodies
148
a chemical messenger that mediates communication between immune cells
Cytokine
149
type of cytokine that is produced rapidly after infection and is secreted by lymphocytes and other cell types
Interleukin
150
Cytokine that stimulate growth, differentiation, and movement of t and b cells, and they are pro-inflammatory and anti-inflammatory
Interleukins
151
What is pus made of?
Neutrophils
152
type of cell that kills unhealthy human cells (trigger apoptosis)
Natural killer cells
153
How does the inflammatory response work?
Mast cells signal the release of histamine, attract macrophages and neutrophils
154
Bind pathogenic cells together to make clumps for phagocytes to eat
agglutination
155
Use of surveillance- how to decrease SSI
surgeon specific SSI data
156
Use of surveillance to decrease HAIs- how to decrease UTI
Unit specific UTI data
157
Is it okay to cohort two people with the same organism if there are no underlying conditions?
Yes
158
What are considerations to make before cohorting?
Ongoing exposure
increased HAI with non permanent staff
no new admits with the infected pts
159
What are important patient education topics?
Hand hygiene
Sharps safety
Germ transmission
Preventing inadvertant contamination
Infection symtpoms
Resp ett.
breathing/ coughing post sugery
Proper pt care
160
Education for visitors
Where are visitors allowed?
Post precautions for visitors in high-risk areas
Teach respiratory ett.
teach hand hygiene
Provide warning for exclusion of ill visitors
