Chpt 15 Flashcards
Observation of traits that an organism is expressing
Phenotypic methods
phenotypic method; physiological/biochemical characteristic
Enzyme production
Antibody response is exploited for diagnostic purposes
OFTEN EASIER THAN TESTING FOR THE MICROBE ITSELF
Immunologic methods
Advantages of genomic methods over phenotypic methods
RAPID RESULTS AND MORE PRECISE
Genotypic methods
A gram stain of a sputum sample from a patient is an example of ___ method of microbial identification
a. Genotypic
b. Immunologic
c. Phenotypic
d. Histologic
e. None of the above
Phenotypic
First step for method of microbial identification is ____
Specimen collection
Aseptic technique is not imperative (t/f)
False, aseptic technique is imperative
When getting a sample, how is it done?
Only infected site should be sampled. Not surrounding areas
When getting a sputum sample, you should avoid___
Contamination with SALIVA
Urine samples should be taken ___ from ____
ASEPTICALLY, from the bladder.
____ taken by the external urethra and collecting the urine midstream
Clean catch!!!
Also known as “first catch”, first voided urine is required for some diagnostic techniques mucous lining of the urethra, vagina or cervix
Dirty catch!!
Skin can be swabbed or scraped with a scalpel to expose deep layers
Skin sample
Tissue fluids is taken by needle aspiration.
Antisepsis of the puncture site is EXTREMELY IMPORTANT
Sterile material sampling
For biochemical testing, ____ is used to see metabolic reactions that cause a ____
Enzyme-mediated, color change
___ causes bacteriophage to infect bacteria in a species-specific and strain-specific way.
Phage typing
During phage typing, cleared areas corresponding to lysed cells don’t indicate sensitivity to that phage. (T/F)
False, it indicates sensitivity to that phage
A few or several hundred colonies of E.coli in a urine sample can indicate normal biota. The amount doesn’t matter (t/f)
False, if there’s only a few it can indicate normal biota, but if there’s several hundred it can mean active infection.
When it comes to a TRUE PATHOGEN, there has to be many colonies in a opportunistic in a sterile site for it to be ruled a disease (T/F)
False, a single colony of a true pathogen in a sputum sample o opportunist in a sterile site is highly suggestive for disease
In vitro testing of serum, urine, cerebrospinal fluid, whole tissues, and saliva for the presence of specific antibiotics.
Serology
Blood plasma without the clotting proteins
Serum
Blood serum containing antibodies against specific antigens
Antiserum
Binding of antibody (Ab) to a specific site or epitope of an antigen (Ag)
Molecular basis of immunologic testing!!!
Antigens are whole cells or organisms such as red blood cells, bacteria, or viruses displaying surface antigens.
Agglutination
____ is used to determine blood compatibility
Agglutination
Antigen examined is a soluble molecule
Precipitation
Lateral flow test found in drugstore pregnancy test and rapid strep test in doctor’s office
Immunochromatography!!!!
Used to diagnose autoimmune disorders and determine past exposure to certain diseases
Antibody titers!!!
Ag-Ab technique for identifying, classifying, and subgrouping certain bacteria into categories called serotypes
Serotyping!!!
___ is highly specific, often used to confirm used to specific but more sensitive or screening test!!!!
Western blot test!!
HIV screening test ELISA is positive then get the more sensitive and accurate western blot!! (t/f)
True
Monoclonal antibodies labeled by fluorescent dye
Fluoroscent antibodies (FAbs)
UNKNOWN TEST SPECIMEN or antigen is fixed to a slide and exposed to a FAb solution
Direct testing
Known antigen is added to the test serum
Indirect testing!!
___ is a common test used for antibody screening for HIV, various rickettsial species, hepatitis A and C, and helicobacter.
*Known antigen
Indirect Elisa test
For a ____ test, verification test with a ____ may be necessary
Indirect Elisa, Western Blot
__ test is a known antibody
Direct Elisa
- Small amount of purified protein derivate (PPD) from mycobacterium tuberculosis is injected into skin.
- Example of ___
Tuberculin reaction. Example of IN VIVO TESTING
Property of a test to focus only!!
Specificity!!
Detection of even minute quantitities of antibodies or antigens in a specimen !!!
Sensitivity!!!!
Direct Elisa detects ____ and indirect Elisa detects ____ from patient samples
Antigens; antibodies!!!
___ will become so cheap and routine that we will soon be doing it with every patient to find microbes causing symptoms
Whol-genome sequencing
Rapid and highly accurate microbial identification within minutes. Analyses FINGERPRINT
Mass spectrometry
___ Are being used more frequently lately to find areas of localized infection in deep tissue
Imaging scans (MRI, CT scan, and PET scans)
If the seven genes are active, what does the prescriber does?
Prescribes an antibiotic
If the seven genes are not active, then the prescriber __
Knows symptoms are caused by virus, and therefrore cannot be helped by antibiotics.
The new diagnostic strategy is an incredibly useful too because___
Majority of antibiotic prescription are incorrectly prescribed for conditions that are not caused by bacteria.!!!
Which of the following technologies detects microbes via protein fingerprints?
a. Nucleic acid sequencing
b. Mass spectrometry
c. Microarrays
d. Imaging
c. Immunofluorescnce
Mass spectrometry
NCLEX1. A RN is training a new staff nurse about proper specimen collection. Consequences of improper specimen collection may exclude all of the following, except:
a. a delay in appropiate treatment
b. exposing the patient to an unnecessary procedure
c. having to repeat the test
d. putting other patients at risk for incorrect treatment
e. putting the patient at risk for incorrect treatment
Putting other patients at risk for incorrect treatment
NCLEX2. A clinical form used to report data on a patient specimens may include:
a. antibiotic history
b. patient symptoms
c. marital status
d. date and time of specimen collection
e. a,b, and,d
f. b,c, and d
Antibiotic history
Patient symptoms
Date and time of specimen collection
NCLEX3.When determining the clinical significance of cultures:
a. the number of microbes is significant
b. the presence of a single colony of a true pathogen may indicate the presence of the disease if the culture comes from a site known to be sterile
c. the repeated isolation of a relatively pure culture of any microorganism can mean it is an agent of disease, although this is not always the case
d. a range of test may be needed to identifiy a pathogen
e. all of the above
All of the above
- When using pulse-field gel electrophoresis, mutations in a microbe’s genome will show as:
a. a different pattern of bands
b. nonfluoerescent bands
c. missing bands
d. all of these
A different pattern of bands
- Mass spectrometry identifies microbes via:
a. fluorescent antibodies
b. cell surface carbohydrates
c. protein fingertips
d. DNA prolifting
Protein fingertips
- Which category of diagnosis is represented by studying a microbe’s utilization of nutrients?
a. phenotypic
b. genotypic
c. immunologic
d. none
Phenotypic
- Which of the following diagnostics techniques is most likely to be affected by changes in growth conditions of specimen?
a. phenotypic
b. immunologic
c. genotypic
Phenotypic
- Which of the following techniques is most likely to reveal that an infection is in biofilm form?
a. ELISA
b. whole-genome-sequencing
c. PFGE
d. Imaging
Imaging
- Bacterial infection causes the expression of different human genes than does viral infection
a. true
b. false
True
- A test that results in a ver large number of false positives probably has an unacceptable level of:
a. sensitivity
b. specificity
Sensitivity
