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A Murine Model of Group B Streptococcus Vaginal Colonization
Published on: November 16, 2016
The necessity of both anorectal and vaginal cultures for group B streptococcus screening during pregnancy
J D Quinlan1, D A Hill, B D Maxwell
1Department of Obstetrics and Gynecology, Florida Hospital Family Practice Residency, Orlando 32803, USA.
Insights
Screening pregnant patients for Group B streptococcus (GBS) using both vaginal and anorectal cultures is crucial. Nearly one-fifth of GBS-colonized women had negative vaginal but positive rectal cultures, highlighting the importance of dual-site screening.
Area of Science:
- Obstetrics and Gynecology
- Neonatal Health
- Infectious Disease Screening
Background:
- Neonatal Group B streptococcus (GBS) sepsis is a significant concern, affecting approximately 2 in 1000 newborns.
- Current Centers for Disease Control and Prevention (CDC) guidelines recommend screening and treatment during pregnancy to reduce neonatal GBS infections.
- Patient reluctance to undergo anorectal cultures presents a challenge to current screening protocols.
Purpose of the Study:
- To evaluate the impact of combined vaginal and anorectal Group B streptococcus (GBS) cultures on patient management.
- To determine if dual-site GBS culturing alters clinical decisions compared to vaginal cultures alone.
Main Methods:
- A prospective study was conducted involving 222 pregnant patients between 35 and 37 weeks' gestation.
- Vaginal and anorectal cultures for GBS were obtained from all participating patients.
- Data on culture results and subsequent management decisions were collected.
Main Results:
- Overall, 54 patients (24.3%) tested positive for GBS colonization.
- A significant finding was that 10 of these women (18.5%) had negative vaginal cultures but positive anorectal cultures.
- This indicates that relying solely on vaginal cultures would miss a substantial proportion of GBS-colonized individuals.
Conclusions:
- Dual-site screening, including both vaginal and anorectal cultures, is recommended for accurate Group B streptococcus (GBS) detection in pregnant patients.
- Healthcare providers should consider this comprehensive approach to ensure appropriate intrapartum antibiotic prophylaxis.
- Implementing dual-site culturing can improve the effectiveness of GBS screening protocols and potentially reduce neonatal sepsis rates.
Background:
Group B streptococcus (GBS) sepsis affects approximately 2 of every 1000 newborns. In an effort to decrease the incidence of neonatal GBS infection, the Centers for Disease Control and Prevention have established guidelines for screening and treatment during pregnancy. One strategy includes obtaining both vaginal and anorectal GBS cultures, then treating patients whose cultures are positive. Many of our patients are reluctant to undergo anorectal cultures. We conducted a study to determine whether performing cultures of both the vagina and anorectum would change patient management.
Methods:
We obtained vaginal and anorectal GBS cultures from 222 consecutive patients at 35 to 37 weeks' gestation.
Results:
Fifty-four patients (24.3%) had positive GBS cultures. Of those women, 10 (18.5%) had negative vaginal but positive rectal cultures. Thus, nearly one fifth of the patients with GBS colonization would not have received intrapartum antibiotics if only vaginal cultures had been performed.
Conclusions:
Health care providers caring for pregnant patients should consider obtaining both vaginal and anorectal cultures when screening for Group B streptococcus.
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