Test Code LAB0280610 Group B Streptococcus, PCR
Methodology
Polymerase Chain Reaction (PCR) utilizing the Cepheid GeneXpert Dx System
Useful for the rapid detection of group B streptococcal antigen directly from cervical /vaginal swabs and rectal/vaginal swabs from preterm and intrapartum maternity patients.
The Xpert GBS Assay is used for patients in Labor with no known Group B Strep Status
Performing Laboratory
CentraCare Laboratory Services
Specimen Requirements
Submit only 1 of the following specimens:
Specimen Type: Vaginal (Cervical/Vaginal)
Container/Tube: Cepheid GBS Collection Device; swabs in transport container
Specimen Volume: Swabs
Collection Instructions:
1. Wipe away excessive amounts of secretion or discharge.
2. Remove both marked swabs from transport container.
3. Carefully insert both marked swabs into vagina. Sample secretions from mucosa of lower 1/3 of vagina. Rotate swabs 3 times to ensure uniform specimen on both swabs.
4. Using same marked swabs, carefully insert both swabs approximately 2.5 cm beyond anal sphincter, and gently rotate to sample anal crypts.
5. Place both marked swabs in transport container.
6. Label container with patient’s name (first and last), medical record number, date and actual time of collection, and type of specimen.
7. If specimen will be processed within 24 hours, store at ambient temperature. If >24 hours, refrigerate specimen until testing is performed. Specimen stored at 2° C to 8° C is stable for up to 6 days.
Specimen Type: Vaginal introitus and anoretum (vaginal/rectum)
Container/Tube: Vaginal/Rectal combination swab; Eswab or Culture transport swab with either Stuart or Amies liquid medium
Specimen Volume: Swab
Collection Instructions:
1. Wipe away excessive amounts of secretion or discharge.
2. Remove swab from transport container.
3. Carefully insert swab into vagina. Sample secretions from mucosa of lower 1/3 of vagina. Rotate swabs 3 times to ensure uniform specimen.
4. Using same swab, carefully insert swab approximately 2.5 cm beyond anal sphincter, and gently rotate to sample anal crypts.
5. Place swab in transport container.
6. Label container with patient’s name (first and last), medical record number, date and actual time of collection, and type of specimen.
7. If specimen will be processed in LIM broth for enrichment within 24 hours, store at ambient temperature. If >24 hours, refrigerate specimen in LIM broth for enrichment until testing is performed. Specimen stored at 2° C to 8° C is stable for up to 6 days.
Specimen Transport Temperature
Ambient <24 hours/Refrigerated 6 days
Reference Values
Negative (reported as positive or negative)
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
87653