The pathogenicicity of Staphylococci from clinical specimens has been largely decided by detection of some type-specific bacterial metabolites such as catalase, coagulase, mannitol decomposing enzyme, and the characteristic resistance to high salt concentration, etc.
Among many measurable bacterial metabolites, detection of some important enzymes play the kev role in determining the pathogenicicity of the organism in the clinical laboratories. They are activities to mannitol and to fresh rabbit or human plasma. It is widely accepted that the coagulase positive Staphylococci are said to be Staphylococcus aureus which stands as clinically pathogenic.
Mannitol fermenting action of Staphylococci is very closely related with the production of coagulase, furthermore, this character is often used to differentiate between the pathogenic Staphylococci and the non-pathogenic ones. Mannitol fermentation test and coagulase test are mostly done individually utilizing two separate test procedures.
The experiment has been focused to see whether these tests could be performed simultaneously using a `look and say´ system pattern omitting any other testing procedures. ´Mannitol-Plasma combined agar medium was designed and tested a total number of 40 known Staphylococci strains, 20 coagulase positives and 20 coagulase negatives, with the `one-look plating method´, and the following data were obtained.
1. The results of mannitol broth fermentation test showed wider variation in coagulase negative strains that of coagulase positive strains.
2. The use of 7.5% NaCl agar should not be much emphasized in determination of pathogenic Staphylococci identification procedures within the genus.
3. The agreement in the mannitol fermentation pattern and coagulase production between the individual tests and the mannitol-coagulase medium was in acceptable range as far as diagnostic bacteriology is concerned.
4. The well initiated quality control system within the criteria of clinical bacteriology is strongly suggested to render more precise and uniform classification.
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