Infectious Process Flashcards
What is virulence
Commonly recognized as the measure of the microbes ability to invade and create disease and a host
Ability of the host to survive
Ability to transmit to a new host
Ability to hear to a structure that can cause infection
Mechanism for proliferation
Invasion and dissemination
Factors to consider when cohorting patients
Common risk factors
Common exposure to communicable disease
Prevention of contact between patients known to be infected
What regulates cell mediated immunity system
T lymphocytes and mono nuclear phagocytes
What is he humoral immunity
Antibody response
What bacteria excretes exotoxins
Exotoxins are secreted by gram-positive bacteria
Name the characteristics of gram-positive bacteria
Heat inactivated
neutralized by specific antibody
possess enzymatic activity
What is an endotoxin complex
Made up of bacterial proteins lipids and polysaccharides that remain firmly within the bacteria
Gram - bacteria
Not always destroyed by heat autoclave
Sets off cascade of responses
Cholera toxin increases fluids in the GI tract
List some characteristics of gram-negative bacteria
Resist inactivation by heat partially neutralized by antibodies
send off Cascades of responses such as fever swelling pain shock. they complement the cascade of cytokines release
What is the function of the thymus during cellular immunity response
The thymus transforms T lymphocytes into mature CD4 helper helper lymphocytes and CD8 cytotoxic lymphocytes
What type of cell kills virus cells
CD8 cells are considered virus killing cells
Where do the CD4 cells populate
Bone marrow, spleen, and lymph nodes
What type of cells are found in the skin and mucous membranes
Langerhans cells
What is lysozyme?
Low activity enzyme secreted by mucous membranes
Kills some gram neg bacteria
Name the three types of granulocytes
Neutrophil
eosinophils
Basophils
What is the First cell to arrive at the site of an inflammatory process
Neutrophil
What cells have no defined role to help resistant infection
Basophils
Contain histamine
What’s so participates in an allergic response and contains histamine
Basophils
What is the response of an eosinophils?
Defense against parasites
What is the left shift
Lab finding of increased numbers of immature neutrophils and the peripheral blood
What is the definition of leukocytosis
White blood cell count of greater than 10,000
What is leukopenia
White blood cell count less than 4000
How to determine absolute neutrophil count
Multiply the cumulative percent of mature and immature PMN and times the total white blood count
How to calculate absoulute neutrophil count
ANC = Total WBC x (segs + bands) / 100
Example
Total WBC 400/mm segs 75% bands 10%
What is the normal white blood count number
4000 to 10,000 cells per cubic millimeter (cumm)
Immunocomprosmised determined by ?
Host defense defects
Type of immunological abnormality induced by an agent
Dose, duration, and temporal sequence of immunosuppressive therapy
Neutropenia or lymphopenia
State of humoral or cellular host defense
Integrity of skin
Metabolic factors
Infections
What type of bacteria is carried on fruits/veggies?
Gram neg
Salads test + for P aeruginisa, e. Coli, klebsiella
What method is best for environmental culturing?
Qualitative or quantitative
Quantitative is better because it determines the amount.
Name 2 ways to determine organism relatedness
Phenotypic or genotype can
Name two types of lymphocytes
T cell - cellular immunity - mature in thymus
B cell - humoral immunity - mature in the bone
T lymphocytes
Start in bone marrow, migrate to the thymus during fetal development,
Mature to the thymus, and produce T cells.
What does sed rate determine?
Increased with Inflammation and infection
RBC or erythrocytes fall to the bottom - the rate at which they fall is the ESR rate
Exotoxins
Protein secreted by gram - or +
Results in cell death and stimulates T cell production causing the cytokines cascade
Exotoxin
Secreted by gram + bacteria
Susceptible to heat activation autoclave kills
Neutralized by antibody
Enzymatic activity
Endotoxin
Gram negative bacteria Not destroyed by autoclaving Partially neutralized by antibody May possess enzymatic activity Sets off cascades of responses Examples cholera
B lymphocytes
Originate in fetal liver and bone marrow. Populate in spleen and lymph nodes
Humoral immunity
IgG
IgM
What are cytotoxic T cells?
Destroy virally infected cells and tumor cells
CD8 T cells
What are memory cells
Antigen specific T cells
Persist long term after an infection has resolved
Memory against previous infections
CD4 or CD8 cells
What are natural killer cells
Produce cytokines
Eliminate some tumor cells
Cells infected with herpes viruses
What is regulatory T cells
Shuts down T cell mediated immunity
What is helper t cells
Assist WBC in immunologic process
Maturation of B cells
WBC Counts Normal range Leukocyte sis Leukopenia Neutropenia
Normal 4000-10,000
Leukocytosis >10,000
Leukopenia < 4,000 cells/mm3
Neutropenia < 1000
Mechanisms of antivirals
Inhibition of formation of DNA precursors
Interference with viral uncoating
Conference of viral resistance on uninfected cells
DOES NOT AFFECT THE CELL WALL
