f We compared the Portrait Toxigenic C. difficile Assay, a new semiautomated sample-to-result molecular test, to a toxigenic bacterial culture/cell cytotoxin neutralization assay (TBC/CCNA) for the detection of toxigenic Clostridium difficile in 549 stool specimens. Stool specimens were also tested by one of three alternative FDA-cleared molecular tests for toxigenic C. difficile (Xpert C. difficile, Illumigene C. difficile, or GeneOhm Cdiff). The sensitivities and specificities of the molecular tests compared to TBC/CCNA were as follows: 98.2% and 92.8% for the Portrait assay, 100% and 91.7% for the Xpert assay, 93.3% and 95.1% for the Illumigene assay, and 97.4% and 98.5% for the GeneOhm assay, respectively. The majority of Portrait false-positive results (20/31; 64.5%) were also positive for C. difficile by an alternative molecular test, suggesting an increased sensitivity compared to the culture-based "gold standard" method. The Portrait test detected an assay input of 30 CFU in 100% of spiked samples and detected an input of 10 CFU in 96.7% of samples tested.

Acute pharyngitis is a nonspecific symptom that can result from a number of viral or bacterial infections. For most etiologies, symptoms are self-limited and resolve without lasting effects; however, pharyngitis resulting from infection with Streptococcus pyogenes (a group A Streptococcus [GAS]) can be associated with serious sequelae, including acute rheumatic fever and acute glomerulonephritis. Rapid accurate detection of GAS in pharyngeal specimens from individuals suffering from pharyngitis aids in the management and selection of antibiotic therapy for these patients. A total of 796 pharyngeal swabs were collected at three separate clinical centers. Each specimen was analyzed using the illumigene group A strep DNA amplification assay (Meridian Bioscience Inc., Cincinnati, OH). To confirm GAS identification, the results were compared to those from direct and extracted culture methods using Gram staining and a GAS-specific latex agglutination test. Discrepant results were resolved using an alternative nucleic acid amplification test. The prevalence of culture-detected GAS in this study was 12.8% (102/796 specimens). The illumigene assay detected GAS in 74/74 direct culture-positive specimens (100% sensitivity) and 100/102 extracted culture-positive specimens (98.0% sensitivity). GAS was detected by the illumigene assay in an additional 42 specimens that were direct culture negative (94.2% specificity) and 16 specimens that were extracted culture negative (97.7% specificity). Discrepant analysis using an alternative molecular assay detected GAS nucleic acid in 13/16 (81.3%) false-positive specimens and 1/2 false-negative specimens, resulting in a final sensitivity of 99.0% and a specificity of 99.6% for the detection of GAS in pharyngeal swabs using the illumigene assay.

A new, commercially available enzyme immunoassay for the detection of toxin A in stool specimens, the Premier Clostridium difficile Toxin A test (Meridian Diagnostics), was evaluated using 228 diarrhoeal stool specimens. Using a cytotoxin assay on HeLa cells as the reference method, this new test resulted in a sensitivity of 88% and a specificity of 95%. Using the presence or absence of a toxigenic strain in the stools as the reference method, the sensitivity was similar to that of the cytotoxin assay (71.7+ versus 70.5%) and the overall correlation was even better (89.4% versus 82%). The Premier Clostridium difficile Toxin A assay is rapid and easy to perform and is an excellent alternative to the usual toxin B assay.

Rectal/vaginal specimens (n ‫؍‬ 97) were collected in parallel using ESwab and Liquid Stuart (LS) rayon fiber wrapped swab collection devices. Each collection device was used to directly inoculate culture medium and LIM broth. Medium inoculation by ESwab was conducted using the Walk-Away specimen processor (WASP). Medium inoculation by the LS device was conducted manually. The sensitivities of ESwab and LS upon direct plating were 93.8% and 87.5%, respectively, and increased to 96.9% and 90.6%, respectively, following broth enrichment.T ransient colonization of the female urogenital tract by Streptococcus agalactiae, or group B Streptococcus (GBS), is a recognized risk factor for the development of neonatal infections acquired during the birthing process. These infections are characterized by onset of sepsis, pneumonia, and meningitis within the first 7 days of life and carry a mortality rate of up to 7% (1, 2). While GBS has been associated with bacteremia, soft tissue infections, pneumonia, and meningitis in adults (3), carriage is typically asymptomatic, with a point prevalence of 10 to 30% in pregnant women (2, 4-6). The identification of GBS during routine prenatal screening aids in decreasing the incidence of invasive GBS disease in newborns through the administration of intrapartum antibiotic prophylaxis in women with a positive GBS test result (7). Further, the screening of pregnant women at 35 to 36 weeks gestation has been recommended by Centers for Disease Control and Prevention (2). Therefore, sensitive methods for detecting GBS in routine prenatal screening specimens are a key component in preventing neonatal disease (2).The use of enrichment broth, selective and chromogenic medium, and molecular diagnostics (6,(8)(9)(10)(11)(12)(13) has increased the sensitivity of GBS detection; however, the initial collection and processing of specimens have largely remained unchanged. Advancements in technology and automation in the clinical microbiology lab have made available more efficient methods for specimen collection and processing, which have the potential to improve the sensitivity of screening and recovery of GBS and other pathogens (14-18). The introduction of ESwab (Copan Diagnostics, Murrieta, CA), when used in combination with the Walk-Away specimen processor (WASP) (Copan Diagnostics), has the potential to improve the efficiency and reproducibility of specimen collection, processing, and pathogen recovery through increased sensitivity, specificity, and reduced turnaround time (14-19). Traditional fiber wrapped swabs coupled with nonnutritive transport medium, such as Liquid Stuart or Amies Gel, aid in the preservation of microorganisms during transit to the clinical laboratory; however, the inefficient transfer or release of microorganisms from a traditional fiber swab may reduce the overall sensitivity of the diagnostic procedure. In contrast, flocked swabs are constructed with a solid bulbous head that is covered in fibers protruding perpendicularly to the swab shaft. The combination of a liquid...

By using cell morphology, arginine dihydrolase, and gas production in de Man, Sharp, Rogosa broth, 122 isolates of vancomycin-resistant lactic bacteria from humans were assigned to five profiles, allowing us to distinguish Pediococcus, homofermentative and heterofermentative Lactobacilus, and Leuconostoc species. The absence of L-(+)-lactic acid, as detected spectrophotometrically, was confirmatory for Leuconostoc species. API 50 CHL panels were useful for the identification of LactobaciUus species.