Rapid Diagnostic Test for Detection of Group B Streptococcus in Pregnancy
Condition: Streptococcus Infection; Pregnancy
MeSH terms: Streptococcal Infections
Study type: Observational

Summary: 
      This study evaluates the use of a new method of growing and detecting Group B streptococcus
      in pregnant women. This new method utilizes sandwiched-membrane petri technology and has the
      advantage of detecting GBS in less than 6 hours, with less cost, and the potential of
      allowing antibiotic sensitivities to be performed.
    

Detailed description: 
      Intrapartum infection with group B streptococci (GBS) may lead to untoward neonatal sequelae
      such as pneumonia, septicemia, and meningitis. Several clinical trials have demonstrated that
      the use of intrapartum intravenous antibiotic prophylaxis (with penicillin being the agent of
      choice due to a narrower spectrum of antimicrobial activity) is highly effective to prevent
      early-onset neonatal GBS infections. It has been estimated that 10% to 30% of all pregnant
      women are GBS carriers, and it is likely that GBS colonizes virtually every female at some
      point. Consensus guidelines from the Centers for Disease Control and Prevention (CDC),
      American College of Obstetricians and Gynecologists (ACOG), and the American Academy of
      Pediatrics, recommend prenatal screening at 35 to 37 weeks of gestation and chemoprophylaxis
      at delivery based upon this culture result. The CDC-recommended method for detecting GBS
      colonization involves collecting a combined vaginal and rectal specimen and culturing the
      organism in a selective broth medium, followed be subculturing onto blood agar plates.

      However, this traditional method of culture takes up to 72 hours for results to be available.
      With 12.8% of patients experiencing a preterm delivery prior to when a GBS screening occurs,
      and up to 15% of term pregnancies not having routine GBS screening performed, a significant
      portion of women present with unknown GBS status at the time of potential delivery. These
      clinical situations require obstetricians to utilize a risk-based strategy that has been
      shown to be only half as effective as culture-based screening. Thus, a need exists for a
      rapid detection method for GBS.

      Recent research has focused on polymerase chain reaction (PCR) based methods for detection of
      GBS. Sensitivity for detection of GBS by the PCR assay has ranged from 87% to 91%. These
      methods are limited by high cost, and inability to perform antibiotic sensitivities for GBS
      (in women with a penicillin allergy). New technologies, called bionanopore (BNP) and
      bionanofilter (BNF) are rapid, microbial detection systems that utilizes sandwiched-membrane
      petri technology. These have the advantage of detecting GBS in less than 6 hours, with less
      cost, and the potential of allowing antibiotic sensitivities to be performed.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Pregnant patients who present to the UT resident or attending clinic between 35-37 weeks
        for routine follow-up will be asked to enroll.
      
Biospecimen description: 
      Specimens are to be retained for one month, frozen in LIM broth, and will be held for use if
      reprocessing specimens is required.
    
Keywords: GBS, Streptococcus, .; Group B