Faster Test For Group B Strep Infection Available For Newborns At Magee
PITTSBURGH, September 23, 2003 Women in active labor at Magee-Womens Hospital of the University of Pittsburgh Medical Center now have the option of accurate and rapid testing for a group B streptococcal infection (GBS), a common bacterial infection that can be deadly for newborns.
GBS infection is a leading cause of serious illness and death for babies. It is the most important risk factor involved in neonatal sepsis, which has a mortality rate as high as 50 percent if it is untreated.
Yet it can be preventable with timely testing to determine whether the mothers genital tract has been colonized with the bacteria which can be transmitted to the fetus during birth and appropriate treatment, said Jeanne A. Jordan, Ph.D., associate professor of pathology at the University of Pittsburgh School of Medicine and associate director of the Magee-Womens Research Institute.
Since 1996, women have been commonly screened for GBS status between 35 and 37 weeks of gestation. Up to 30 percent are found to be positive for GBS colonization. Even so, their bacterial population can change quickly, Dr. Jordan said. Previous testing took two to three days to complete. The newest molecular assay can be done in 40 minutes.
The value of molecular group B strep testing is greatest for the woman who has received little or no prenatal care or who is in preterm labor and hasn't been screened or doesn't know her third-trimester screen result, said Dr. Jordan. This woman can now be screened for GBS at the time of labor and delivery and avoid unnecessary antibiotic treatment if she is not colonized with GBS.
Developed by Infectio Diagnostic Inc. of Quebec City, Canada, and Sunnyvale, Calif.-based Cepheid, the IDI-Strep B molecular assay test was approved by the U.S. Food and Drug Administration in November 2002. Magee was one of five centers that took part in a study to determine whether using a real-time assay during labor and delivery could possibly make a difference in outcome.
From our participation in the IDI-Cepheid trial, we discovered that during labor and delivery, 9 percent of patients changed their GBS colonization status since the third trimester screen, Dr. Jordan continued, adding that about half of those changed from GBS-negative to GBS-positive. The remainder switched from positive to negative.
The potential impact on the woman who switches from GBS-negative to GBS-positive is the risk of transmitting GBS to her baby during labor and delivery, she said.
In addition, Dr. Jordan said, it is important to avoid giving antibiotics when such treatment is unnecessary, since it is estimated that nearly 20 percent of GBS microbes now are antibiotic-resistant.