Examine classification and nomenclature, morphology, isolation and identification procedures, clinical significance and antimicrobial susceptibility of staphylococci.
Version Date: August 2011
PEP hours: 11
CPS credits: 0
Course Type: Express
Start Date: Upon registration
Completion: Up to 52 weeks
Delivery: PDF via email
Equipment: Computer with Internet is required
- 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.
Author/Instructor: Helen Smith, MLT
Version Date: August 2011