26599 Group B Strep Screen, Nucleic Acid Test

​GBS Screen​

​Screening of Group B streptococci carriage in pregnant females.

​A swab specimen should be collected first from the lower vagina and then from the rectum without use of a speculum.

- Submit one ESwab collection device

- Other Amies medium swab types are acceptable: collect one swab 
See eSwab collection video for more information​​

'ESwab' is a trademark of Copan Diagnostics.

For more information on Specimen Collection Media/Swab, see Specimen Transport Pictorial.​

This is a qualitative PCR assay that incorporates the use of LIM selective enrichment broth to detect Group B streptococci.  Results will be reported as Positive, Negative or Indeterminate.

The American Society for Microbiology has published guidelines for optimal practices for screening for Group B streptococcal (GBS) carriers.  These guidelines recommend universal prenatal screening for vaginal and rectal GBS colonization of all pregnant women at 36-37 weeks unless intrapartum GBS prophylaxis is already recommended due to identified risk factors.

For penicillin allergic patients, screening can be ordered with automatic reflex to susceptibility testing (Test Code: GBSNAT-RFX).

Susceptibility results will be available 48-72 hours after positive GBSNAT result.  If no Group B Streptococci is isolated on reflex culture the report will indicate “A positive test result obtained by PCR testing (GBSNAT) does not indicate the presence of viable organism; this testing is more sensitive than culture".

 
 (ASM Guidelines for the Detection and Identification of Group B Streptococcus July 29, 2021)