Group A strep is PYR positive. However, I've only ever used PYR
routinely in conjunction with Group D strep (enterococcus). If one uses
a bacitracin disc and gets an equivocal result, and uses a SXT disc in
conjunction to ID Group A (which should be S to bacitracin and R to SXT)
one can use the PYR as a kind of confirmatory. My current lab uses
latex agglutination for all beta strep testing and doesn't use
bacitracin or SXT discs at all.
Perhaps there are other micro labs using PYR for Group A testing, but
I've never worked anywhere that used it for that.
Is there anyone else out there that does?
Judy Dilworth, M.T. (ASCP)
Patrick Druggan wrote:
>> Did the PYR test displace the bacitracin suseptibility test, or is the
> method used dependant on the lab carrying out the identification?