Coagulase-positive organisms should be tested for catalase activity and examined by gram stain to determine morphology and gram reaction. If the tubes are not read until 24 hours of incubation, reversion to a false-negative might result.
Negative tubes must be held overnight because some S.
aureus strains require longer than 4 hours to form a clot.
Once reconstituted, Coagu Staph™ can be stored at 2-8ºC. Reconstituted plasmas, if kept uncontaminated, retain their activity for five days when stored at 2-8ºC. Negative tests at 4 hours should be held at room temperature for a total of 24 hours before reporting results. Place a drop of coagulase plasma on a clean, dry glass slide. Place a drop of distilled water or saline near the drop of plasma as a control. With a sterile loop or wooden stick, emulsify an amount of the isolated colony being tested into each drop, inoculating the water or saline first. Clumps that will not mix uniformly into coagulase plasma indicate a positive test whereas a uniform suspension is indicative of a negative test.
for up to 5 days or aliquot into 0.5ml amounts and stored at -20ºC. Reconstituted plasma should be frozen immediately after use. This product should not be used if there is any sign of deterioration, or if the expiration date has passed. and up to 30 days when aliquoted and stored at -20ºC., not exceeding the expiration date on the label. Reconstitute each vial of Coagu Staph™ using sterile deionized water as follows: 2. Clumping in both tests indicate that the organism autoagglutinates and is unsuitable for the slide coagulase test.
Slide Coagulase Test: The slide agglutination technique may lead to false-positives, since some strains such as S. In addition, spontaneous agglutination may occur when rough cultures are used.
A positive slide coagulase test result is valid only for strains of Staphylococcus spp. Autoagglutinating strains of staphylococci require an alternative method for testing for S. Standard microbiological equipment such as inoculating loops, sterile tubes, sterile pipets, sterile deionized water, incinerators, incubators, slides, other culture media, etc., as well as serological and biochemical reagents, are not provided.
The air in the tube was evacuated, and when a high voltage was applied, the tube produced a fluorescent glow.
Roentgen shielded the tube with heavy black paper, and discovered a green colored fluorescent light generated by a material located a few feet away from the tube.
Aliquot 0.5ml of reconstituted Coagu Staph™ into sterile test tubes using a sterile pipette. Using a culture that is less than 24 hours old, inoculate the Coagu Staph™ by emulsifying one loopful (2-4 colonies) of bacteria from a non-inhibitory agar plate into the tube of plasma. When autoagglutination is observed, the tube coagulase test should be employed as an alternative to the slide agglutination test.
Store Coagu Staph™ that will not be used immediately at a temperature below 20ºC. Tube Coagulase Test: Results should be read at 4 hours.
Do not use cultures that are more than 24 hours old. All negative tests should be held at room temperature for a total of 24 hours before recording results.