Light microscopy aids in the observation of these items.
cell shape, size, and arrangement; Gram stain reaction, acid-fast reaction; endospores, granules, and capsules
What can you use to pinpoint harder to see characteristics such as cell wall, flagella, pili, or fimbriae?
Name the biochemical characteristics used to diagnose infectious agents. (5)
(1) Enzyme production, (2) fermentation of sugars, (3) capacity to digest complex polymers, (4) production of gas, (5) sensitivity to antibiotics
Which method produces more rapid results?
Viable Noncultured (VNC)
microbes that can't be grown in the laboratory that are identified by genotypic methods
patient sample is tested for the presence of specific antibodies to a suspected pathogen
A Gram stain of a sputum sample from a patient is an example of a ______ method of microbial identification. A. genotypic B. immunologic C. phenotypic D. histologic E. None of the choices is correct.
"Clean Catch" Urine Sampling (describe the method)
taken by washing the external urethra and collecting the urine midstream
How to collect a skin sample
skin can be swabbed or scraped with a scalpel to expose deeper layers; wounds must be cleansed prior to swabbing
Sterile Material Sampling
blood, cerebrospinal fluid, and tissue fluids must be taken by STERILE NEEDLE ASPIRATION
Signs of microbial infections (4)
(1) fever, (2) wound exudate, (3) mucus production, and (4) abnormal lesions
place the isolated microbe into a preliminary category
pinpoint the microbe’s identity
Results are entered into ______
a summary patient chart
Tests involved when starting with patient analysis: (3)
(1) immunologic and serologic tests on blood; (2) in vivo tests for reaction to microbe; (3) clinical signs and symptoms
Direct Testing (Microscopic) (4)
(1) Gram-stain; (2) Acid-fast stain; (3) Fluorescent Ab stain; (4) Gene probes
Direct Testing (Macroscopic) (2)
(1) Direct Antigen; (2) Gene probes
Tests on Isolates (6)
(1) Biochemical; (2) Serotyping; (3) Antimicrobial Sensitivity; (4) Gene probes; (5) Phage testing; (6) Animal inoculation
Care should be taken to avoid contamination with ______ when taking samples from a patient. air water droplet nuclei normal microbiota None of the choices is correct.
Stains most often used when diagnosing
Gram-stain and Acid-fast
used to enrich a pathogen present in small numbers or is easily overgrown
to encourage the growth of only the suspected pathogen
used to identify definitive characteristics and fermentation patterns
pure cultures must be obtained from___________so that subsequent steps in identification will be accurate
Physiological reactions of bacteria to nutrients and other substrates indicates what?
Enzymes are present in bacteria
Enzyme-mediated metabolic reactions often visualized by what?
a color change
Carbohydrate Fermentation shows...?
production of acid and/or gas
Enzyme actions (biochemical tests):
catalase, oxidase, and coagulase
Flow charts based on easily recognizable characteristics (motility, gram-stain, morphology) that helps identify bacteria
Test used when morphological and biochemical tests are insufficient; infects bacteria with bacteriophage to identify certain kinds