Group B Strep (GBS) PCR or Xpert GBS

1. This test is specifically for pre-term labor patients and those who have not had prenatal care.
2. The orderable name is Group B Strep (GBS) PCR or Xpert GBS to differentiate from the existing GBS Screen orderable. The test turnaround time is 1 hour once received in the laboratory.
3. The results appear as: “Positive” or “Negative.”
4. Collection Kit: Item 900-0370, dual swab Liquid Stuart swab. The laboratory provides this collection kit; it is not available from the Materials Department.
5. Collection Steps:
   • Wipe away excessive amounts of secretion or discharge.
   • Remove both marked swabs from the transport container.
   • Carefully insert both marked swabs into the patient's vagina. Sample secretions from the mucosa of the lower one-third part of the vagina. Rotate the swabs three times to ensure uniform sample on both swabs.
   • Using the same marked swabs, carefully insert both swabs approximately 2.5 cm beyond the anal sphincter, and gently rotate to sample anal crypts.
   • Place both marked swabs in the transport container.
6. Stability: Specimens stored at 2–8º C are stable for up to six days. Specimens stored at room temperature are stable for 24 hours. Preferred storage is 2–8º C.
7. For Every Group B Streptococcus PCR ordered CERNER automatically orders a GBS Screen. One dual swab is collected for both tests, a 2nd swab is NOT needed. The laboratory will perform a GBS screen for every GBS PCR ordered.
8. A positive PCR test result does not necessarily indicate the presence of viable organism. It is, however, presumptive for the presence of Group B Streptococcus. The GBS Screen results will confirm the PCR results.