Chapter 15 Flashcards
Signs of microbial infection:
Fever, wound exudate, mucus production, abnormal lesions
How do you identify bacteria in patient specimens or in samples from nature?
Phenotypic, immunologic, genotypic
What is phenotypic?
Considers macroscopic and microscopic morphology, physiology, and biochemistry
-visible trait, non-expensive, 85% accuracy, widely used
What is immunologic?
Analysis of microbe using antibodies or of patients antibodies using prepackaged antigens
-Serological analysis
- immune system, circulatory and lymph system
- more expensive and accurate than phenotypic, few hours to get results
What is genotypic?
Analysis of microbes DNA or RNA - most specific type
-expensive, 100% accuracy, seconds for results
What is presumptive data?
Place the isolated microbe into a preliminary category
What’s confirmatory data?
Pinpoint the microbes identity
Used to enrich a pathogen present in small numbers or easily grown:
Specialized media
Used for nonsterile specimens containing a diversity of bacterial species to encourage the growth of only the suspected pathogen
Selective media
Used to identify definitive characteristics and fermentation patterns
Differential media
Light microscopy aids in the observation of:
- cell shape, size, arrangement
- gram stain reaction, acid fast reaction
- endospores, granules, and capsules
Electron microscopy can pinpoint additional structural features such as:
-cell wall, flagella, pili, frimbriae
Advantages of genomic methods over phenotypic methods?
- culturing of microorganisms is not always necessary
- produces rapid results that are more precise than phenotypic methods
What is viable noncultured(VNC) ?
Microbes that can’t be grown in the lab that are identified by genotypic methods
Monoclonal antibodies (mAabs) can be used in:
- disease prevention
- immunomodulation (could controlling overactive inflammatory responses)
Serology involves:
The study antigen-antibody interactions
Serological reactions have characteristics:
- can help diagnose microbial infections
- titration is the dilution of antigen or antibody solution to the most favorable concentration
- the titer is the most dilute concentration of serum antibody that reacts to its antigen (a rise in the tiger ratio indicates disease)
Agglutination involves:
The clumping of antigens
Hemagglutination is used to:
- determine blood type
- detect viruses that cause agglutination of red blood cells
What is fluorescent antibodies?
Monoclonal antibodies labeled by a fluorescent dye
Gram Stain:
Uses crystal violet, iodine, alcohol, saffranin
Gram + (purple) = protein in cell wall
Gram - (pink) = lipids in cell wall
Presumptive data
Start antibiotics
Titer tests for?
Antibodies
Western blot uses:
Color dyes
Fluorescent test:
Uses fluorescents
