Improved Sensitivity for Molecular Detection of Bacterial and Candida Infections in Blood
Autor: | Thomas G. Laffler, David Metzgar, Lawrence B. Blyn, Donna Toleno, David J. Ecker, Teresa Wakefield, Karen C. Carroll, Natalie J. Kennel, Jose R. Gutierrez, Gregory S. Richmond, Andrea Bacconi, Richard E. Rothman, Christian Massire, Rangarajan Sampath, Heather E. Carolan, Mark Frinder, Michelle A. Baroldi, Megan A. Rounds, Stephen Peterson |
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Rok vydání: | 2014 |
Předmět: |
Adult
Male Microbiology (medical) Spectrometry Mass Electrospray Ionization Lysis Adolescent Bacteremia Polymerase Chain Reaction Sensitivity and Specificity Specimen Handling law.invention Young Adult law medicine Humans Prospective Studies Polymerase chain reaction Whole blood Automation Laboratory biology Candidemia Bacteriology biology.organism_classification medicine.disease DNA extraction Molecular biology genomic DNA Titer Blood Molecular Diagnostic Techniques Female Bacteria |
Zdroj: | Journal of Clinical Microbiology. 52:3164-3174 |
ISSN: | 1098-660X 0095-1137 |
Popis: | The rapid identification of bacteria and fungi directly from the blood of patients with suspected bloodstream infections aids in diagnosis and guides treatment decisions. The development of an automated, rapid, and sensitive molecular technology capable of detecting the diverse agents of such infections at low titers has been challenging, due in part to the high background of genomic DNA in blood. PCR followed by electrospray ionization mass spectrometry (PCR/ESI-MS) allows for the rapid and accurate identification of microorganisms but with a sensitivity of about 50% compared to that of culture when using 1-ml whole-blood specimens. Here, we describe a new integrated specimen preparation technology that substantially improves the sensitivity of PCR/ESI-MS analysis. An efficient lysis method and automated DNA purification system were designed for processing 5 ml of whole blood. In addition, PCR amplification formulations were optimized to tolerate high levels of human DNA. An analysis of 331 specimens collected from patients with suspected bloodstream infections resulted in 35 PCR/ESI-MS-positive specimens (10.6%) compared to 18 positive by culture (5.4%). PCR/ESI-MS was 83% sensitive and 94% specific compared to culture. Replicate PCR/ESI-MS testing from a second aliquot of the PCR/ESI-MS-positive/culture-negative specimens corroborated the initial findings in most cases, resulting in increased sensitivity (91%) and specificity (99%) when confirmed detections were considered true positives. The integrated solution described here has the potential to provide rapid detection and identification of organisms responsible for bloodstream infections. |
Databáze: | OpenAIRE |
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