| Summary: | Group B Streptococcus, or GBS, is a gram positive bacteria commonly found in the gastrointestinal, genital and urinary tract of healthy adults. Between 10% and 30% of all pregnant women are colonized with GBS in the vagina or rectum. While GBS colonized mothers typically show no symptoms or adverse health effects, the bacteria can be passed to their child during labor and delivery. Although significant progress has been made in the identification and treatment of GBS, it remains the leading infectious cause of Page 14 2014 Appalachian Student Research Forum morbidity and mortality among newborns in the United States. The current guidelines recommended by the Center for Disease Control and Prevention (CDC) and endorsed by the American College of Obstetrics and Gynecology (ACOG) is to test pregnant women for GBS colonization between 34-37 weeks of gestation. The current gold standard for identification of GBS colonization is the use of selective enrichment broth (SEB) followed by culture and biochemical testing. Identified concerns with the culture procedure are: 1) the length of time it takes to get the results, 2) the lower sensitivity if the SEB step is left out to improve turn-around-time (TAT) and 3) the limited number of qualified technicians available to perform the complex test. Recently, several semi-automated molecular assays have been developed for identification of GBS which are marketed as having equivalent sensitivity and specificity to SEB followed by culture. The goals of this study were to: 1) validate the sensitivity and specificity of an FDA approved GBS molecular assay (Illumigene, Meridian Bioscience) and 2) evaluate a new testing strategy utilizing SEB followed by the Illumigene GBS assay to see if it offers an improvement in TAT when compared to SEB culture in our in-house microbiology lab and to those sent out to a national reference lab for GBS DNA assay. During the validation process, 20 consecutive samples were submitted to SEB followed by simultaneous in-house culture and Illumigene assay for GBS. The method validation experiments were analyzed using the EP Evaluator version 11 statistical software (Data Innovations). Comparison of TAT was evaluated utilizing a blinded report generated from our Laboratory Information System (Harvest, Orchard Software) for a 2 month period for the GBS tests performed using the SEB followed by Illumigene molecular assay (n=73), in-house SEB followed by culture (n=50) and send-out reference lab GBS DNA assay (n=43) procedures. The TAT (hrs) for each method (Mean±SEM) were determined from the time of collection until result approval. The Illumigene assay had a high sensitivity (100%) and specificity (100%) when compared to SEB followed by culture for identification of GBS. Utilization of the Illumigene assay following SEB significantly (p
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