Staphylococci
Staphylococci (9813-11)
Examine classification and nomenclature, morphology, isolation and identification procedures, clinical significance and antimicrobial susceptibility of staphylococci.
Version Date: August 2011
| Code |
9813-11 |
| Niveau |
Fondamental |
Prix membres
$0
Prix non-membres
$135
Renseignements additionnels
Category: Microbiology, Free
PEP hours: 11
CPS/ART credits: 0
Learning Outcomes:
· Describe the cellular morphology of staphylococci and state criteria for recognition in direct smears of clinical exudate.
· State the optimum temperature, oxygen requirements and suitable media for isolation.
· Describe typical colonies of Staphylococcus aureus (S. aureus) on sheep blood agar.
· Describe the selective and differential properties of mannitol salt agar.
· State two tests with results that usually indicate that a Gram positive cocci belongs to the genus Staphylococcus.
· State the usual result for S. aureus in the slide coagulase test. State the usual causes of false negative results. Explain why a positive test may not always indicate S. aureus.
· State the result of S. aureus for the tube coagulase test and explain why this is the GOLD STANDARD test for this organism.
· Describe the principle of the latex and hemagglutination tests used as screen tests for S. aureus.
· State which group of staphylococci are most likely to give false negative results with rapid screen tests and explain when a tube coagulase test is needed for definitive identification?
· State the usual result of the DNase test for S. aureus and coagulase negative staphylococci. Explain why the DNase test is not a good screen test for S. aureus.
· State the reliability of the thermostable nuclease test for detecting S. aureus and explain why it is not suitable for routine use.
· Describe a screen test for Staphylococcus saprophyticus(S.saprophyticus) including interpretation of results.
· Describe the cellular and colonial morphology of coagulase negative staphylococci.
· State when identification of coagulase negative staphylococci to the species level is required.
· Explain when it may be necessary to distinguish between Staphylococcus and Micrococcus.
· List five tests that may be used to differentiate staphylococci from micrococci and give the typical results for each genus.
· Briefly state what is involved in the definitive identification of coagulase negative staphylococci.
· List and describe common infections caused by S. aureus.
· List and describe three conditions caused by exotoxins of S. aureus.
· Describe the pathogenicity of S. saprophyticus.
· State where coagulase negative staphylococci are found as normal flora and name the most common species isolated.
· Describe the pathogenicity of coagulase negative staphylococci.
· State the current level of resistance of S. aureus to penicillin G and explain what causes this resistance.
· Describe the appearance of zones around penicillin G discs when an organism is producing beta-lactamase.
· State when it may be necessary to test for induced beta-lactamase and describe how this is done.
· List the beta-lactamase resistant penicillins.
· Understand what is meant by methicillin resistant S. aureus (MRSA)
· Explain the term "intrinsically heteroresistant" as it applies to Methicillin Resistant S. aureus.
· State the reason for supplementing media with sodium chloride when performing sensitivity tests.
· Outline the oxacillin agar procedure recommended by CSLI for detecting MRSA.
· State the usual in vivo sensitivity of MRSA to cephalosporins and vancomycin.
· Explain the use of bacteriophage testing and pulsed-field gel electrophoresis.
Instructor: Helen Smith, MLT
Prerequisites: None
Textbook: N/A
Equipment: Computer with Internet is required
Start Date: Upon registration
Completion: Up to 52 weeks
Version Date: August 2011