This week its my turn to post a blogging post of my experience in my lab. For this week I am attached to my company’s satellite lab. A satellite lab is like an assistant towards the main lab handling samples collected from clinics. However a satellite lab is limited in terms of the number of test that can be done. This is due to a much smaller space to place adequate number of machines. Some machines that is used is also different from the main lab.
However I will be posting about a test, which I did in microbiology department, which I was posted into about 3 weeks ago. It is a routine test to detect the presence of gram-positive Staphylococcus aureus. Staphylococcus aureus is one of the most frequently encountered pathogens in clinical specimens. The rapid distinction between this species to other less virulent Staphylococci is very crucial and vital for an appropriate patient management. The test for the detection of free coagulase production permits the identification of staphylococcus aureus. The test reagent used is PASTOREX STAPH-PLUS to perform the coagulase test.
PASTOREX STAPH-PLUS is a rapid slide agglutination test for the simultaneous detection of the fibrinogen affinity, protein A and the capsular polysaccharides of Staphylococcus aureus.
The principle of PASTOREX STAPH-PLUS test reagent was designed to allow simultaneous detection of the following 3 components:
1 Fibrinogen affinity factor, also referred to as bound coagulase or “clumping factor”
2Protein A, which possesses an affinity for the crystallisable fragment(Fc) of gamma immunoglobumins (IgG).
3 Capsular polysaccharides of Staphylococcus aureus.
PASTOREX STAPH-PLUS reagent is made of latex particles sensitized by fibrinogen and IgG as well as specific monoclonal antibodies raised against capsular polysaccharides of Staphylococcus aureus. The combination of fibrinogen, IgG and anti-capsular monoclonal antibodies in the same reagent allows the recognition of highly encapsulated strains of Staphylococcus aureus as well as poorly encapsulated strains. For highly encapsulated strains, anti-capsular polysaccharides antibodies agglutinate the bacteria. For strains that have lost their polysaccharide capsule, the bacteria are agglutinated by fibrinogen and IgG.
Steps and procedures involved.
1 Place a drop of PASTOREX STAPH-PLUS
2 Inoculate a pure strain of bacteria colony from an agar plate and placed onto a clean glass slide.
3 Mix the reagent and the bacteria colony well
4 Observe for any agglutination. If there is agglutination, it means the bacteria colony is gram-positive Staphylococcus aureus.