what are the classification schemes in identifying streptococcal isolates? please explain each scheme.?

Question

thanks a whole lot!

Answer 1

are you referring to groups a,b,c, and d?

or are you referring to biochemical tests?

in my lab, the first thing we do is a gram stain. if it is a gram positive cocci, then do a catalase. if it is catalase negative, then we do a PYR. if it is PYR positive, it could be an enterococcus. follow-up tests for this are high salt broth (i can't remember the name of it) and bile esculin. we don't test for these in our facility, just give a presumptive ID. another PYR positive organism is group a strep (the strep throat organism). we have an EIA kit to confirm this. if it is PYR negative, then we proceed to test for group b strep on our prenatal patients. we have a PCR test for this. if it is PYR negative, and not group a, group b, or enterococcus, you would suspect a group c or d. we don't test for these. btw, enterococcus is a group d strep, but not all group d strep are enterococci. hope this helps.