Automated quantitative drug susceptibility testing of non-tuberculous mycobacteria using MGIT 960/EpiCenter TB eXiST

Objectives To assess the predictive value of in vitro drug susceptibility testing (DST) in slow-growing non-tuberculous mycobacteria (NTM), knowledge on quantitative levels of drug susceptibility should be available. The aim of this study was to investigate the suitability of the MGIT 960/TB eXiST system for quantitative DST of NTM. Methods We have assessed quantitative levels of drug susceptibility for clinical isolates of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium kansasii by comparing radiometric Bactec 460TB-based DST with non-radiometric DST using MGIT 960/TB eXiST. Results MGIT 960/TB eXiST gives results comparable to those of Bactec 460TB. Conclusions The MGIT 960/TB eXiST appears suitable for quantitative DST of NT

Open Government

Dieses Buch – eine Open-Access-Publikation mit freiem Online-Zugang – bietet Führungskräften und Mitarbeitenden im öffentlichen Sektor sowie Studierenden eine ebenso kompakte wie kompetente Einführung in die wesentlichen Aspekte von Open Government. Das Konzept Open Government (offenes Regierungs- und Verwaltungshandeln) beschreibt einen Kulturwandel von Politik und Verwaltung hin zu mehr Transparenz, Partizipation der Zivilgesellschaft und Zusammenarbeit innerhalb des öffentlichen Sektors als auch mit Akteuren aus Wirtschaft und Wissenschaft. Durch die Digitalisierung und des Angebots offener Daten ergeben sich für Politik und Verwaltung neue Möglichkeiten der Interaktion und der Offenlegung von Entscheidungen. Das Buch bietet einen kompakten Einstieg in Themen wie Transparenz, Bürgerbeteiligung, Zusammenarbeit sowie der Öffnung von Datenbeständen. Ebenso wird die Teilnahme Deutschlands an der Open Government Partnership vorgestellt. Durch direkte Verlinkungen auf vorbildhafte Beispiele für ein offenes Regierungs- und Verwaltungshandeln in der Praxis sowie ein digitales Karteikartensystem wird umfangreiches Wissen anschaulich und zielgerecht vermittelt. Die Leser werden mit Leitbildern, Zielen und Methoden im Bereich Open Government vertraut gemacht und können diese kritisch reflektieren Im Sinne von Offenheit ist dieses Werk eine Open-Access-Publikation mit freiem Online-Zugang. Aus dem Inhalt Open Government – Grundlagen eines offenen Regierungs- und Verwaltungshandelns Transparenz 2.0 Offene Daten und offene Verwaltungsdaten – Öffnung von Datenbeständen Open Budget – Öffnung des Haushaltswesens Bürgerbeteiligung 2.0 Zusammenarbeit 2.0 Aktivitäten Deutschlands in der Open Government Partnership Inklusive kostenlosem Online-Wissens-Quiz mit der Springer Nature Flashcards-App

Detection of Methicillin-Resistant Staphylococcus aureus (MRSA) in Specimens from Various Body Sites: Performance Characteristics of the BD GeneOhm MRSA Assay, the Xpert MRSA Assay, and Broth-Enriched Culture in an Area with a Low Prevalence of MRSA Infections ▿

Universal surveillance upon patient admission is important in reducing the transmission of methicillin-resistant Staphylococcus aureus (MRSA) and associated disease in hospitals. High costs for the health care system in conjunction with MRSA have promoted the development of rapid screening methods to detect MRSA carriers. This study compared two real-time PCR methods, the BD GeneOhm MRSA assay (BDGO) and the Xpert MRSA assay, with broth-enriched culture to define their performance characteristics and rapidity in an area with low MRSA prevalence. In total, 414 swabs from the nose and 389 swabs from the groin from 425 patients were tested. Of those 425 patients, 378 had swabs from both the nose and groin in parallel. Two hundred thirty-one and 194 patients were randomly assigned to the BDGO group and the Xpert MRSA group, respectively. In general, sensitivity, specificity, and negative predictive value (NPV) were high for the BDGO (100%, 98.5%, and 100%, respectively) and the Xpert MRSA (100%, 98.2%, and 100%, respectively), irrespective of whether or not nasal and inguinal specimens were considered alone or combined. In contrast, the positive predictive value (PPV) was lower: before the resolution of discrepant results, the PPVs for nasal and inguinal specimens alone and combined were 87.5%, 86.7%, and 82.4% for the BDGO and 91.7%, 66.7%, and 92.9% for the Xpert MRSA, respectively. After the resolution of discrepant results, PPVs were 93.8%, 93.3% and 94.1% for the BDGO and 91.7%, 88.9% and 92.9% for the Xpert MRSA, respectively. With the BDGO, 4 of 16 carriers were each identified by nasal or inguinal swabs alone, whereas in the Xpert MRSA group, 4 of 13 carriers were exclusively identified by nasal swabs and 2 of 13 were identified by inguinal swabs alone. Both PCR methods showed no significant difference in the number of discrepant results (odds ratio, 0.70 [P = 0.789]), but specimens from wounds and other body sites (axilla, vagina, and throat) produced discrepancies more often than nasal and groin specimens (odds ratios, 4.724 [P = 0.058] and 12.163 [P < 0.001], respectively). The facts that no false-negative PCR results were detected and increased PPVs were found after the resolution of discrepant results point to PCR as the actual gold standard. Since both sensitivity and NPV were exceptionally high for PCR, backup cultures may, therefore, be unnecessary in an area with low prevalence and with a preemptive isolation strategy but may still be useful for PCR-positive specimens because of the lower PPV for both methods and the possibility of susceptibility testing. The median time for analysis, including extraction, hands-on time, and actual PCR was 2 h 20 min for the Xpert MRSA versus 5 h 40 min for the BDGO. Concerning reporting time, including administration and specimen collection, the Xpert MRSA was faster than the BDGO (7 h 50 min versus 17 h)

Quantitative Drug Susceptibility Testing of Mycobacterium tuberculosis by Use of MGIT 960 and EpiCenter Instrumentation ▿

Since numbers of drug-resistant Mycobacterium tuberculosis strains are on the rise, the simple classification into “susceptible” and “resistant” strains based on susceptibility testing at “critical concentrations” has to be reconsidered. While future studies have to address the correlation of phenotypic resistance levels and treatment outcomes, a prerequisite for corresponding investigations is the ability to exactly determine levels of quantitative drug resistance in clinical M. tuberculosis isolates. Here we have established the conditions for quantitative drug susceptibility testing for first- and second-line agents using MGIT 960 instrumentation and EpiCenter software equipped with the TB eXiST module. In-depth comparative analysis of a range of well-characterized susceptible and resistant clinical isolates has allowed us to propose conditions for testing and to develop criteria for interpretation

Systematic Internal Transcribed Spacer Sequence Analysis for Identification of Clinical Mold Isolates in Diagnostic Mycology: a 5-Year Study▿ †

The implementation of internal transcribed spacer (ITS) sequencing for routine identification of molds in the diagnostic mycology laboratory was analyzed in a 5-year study. All mold isolates (n = 6,900) recovered in our laboratory from 2005 to 2009 were included in this study. According to a defined work flow, which in addition to troublesome phenotypic identification takes clinical relevance into account, 233 isolates were subjected to ITS sequence analysis. Sequencing resulted in successful identification for 78.6% of the analyzed isolates (57.1% at species level, 21.5% at genus level). In comparison, extended in-depth phenotypic characterization of the isolates subjected to sequencing achieved taxonomic assignment for 47.6% of these, with a mere 13.3% at species level. Optimization of DNA extraction further improved the efficacy of molecular identification. This study is the first of its kind to testify to the systematic implementation of sequence-based identification procedures in the routine workup of mold isolates in the diagnostic mycology laboratory