Mentor-mentee relationship in clinical microbiology.

Clinical microbiology is a field in constant evolution, with increasing technological opportunities and a growing emphasis on human and social issues. Maintaining knowledge and skills and anticipating future changes is challenging both for laboratory managers and for all the co-workers. Training and succession preparation represents a unique opportunity to adapt/prepare future generations according to the evolutions of the field. The aim of this review is to provide to clinical microbiologists a reflection on ongoing technological and social changes in their field and a deepening of the central role of preparing future generations to these changes through a fruitful mentor-mentee relationship. This narrative review relies on selected publications addressing mentor-mentee interactions in various academic fields, on interview with our colleagues and pairs, as well as on our personal experience. From the qualities and aspects that emerged as necessary for a productive mentor-mentee interaction, we selected and discuss five of them for the mentor: the role and responsibility, the positioning, the vision, the scientific credibility, and the moral credibility, as well as five for the mentee: creativity, flexibility, energy, responsibility, and self evaluation. This review emphasizes the importance of both the scientific and the ethical credibility of the mentor and the mentee as well as the importance of human and social values such as solidarity, equality, equity, respectfulness, and empathy, and might support mentor and mentee in the field of clinical microbiology and also in the field of infectious disease in their intent for a fruitful interaction

Methods for Real-Time PCR-Based Diagnosis of Chlamydia pneumoniae, Chlamydia psittaci, and Chlamydia abortus Infections in an Opened Molecular Diagnostic Platform.

The advances in molecular biology of the last decades have dramatically improved the field of diagnostic bacteriology. In particular, PCR-based technologies have impacted the diagnosis of infections caused by obligate intracellular bacteria such as pathogens from the Chlamydiacae family. Here, we describe a real-time PCR-based method using the Taqman technology for the diagnosis of Chlamydia pneumoniae, Chlamydia psittaci, and Chlamydia abortus infection. The method presented here can be applied to various clinical samples and can be adapted on opened molecular diagnostic platforms

Assessment of SARS-CoV-2 tests costs and reimbursement tariffs readjustments during the COVID-19 pandemic.

While laboratories have been facing limited supplies of reagents for diagnostic tests throughout the course of the COVID-19 pandemic, national and international health plans, as well as billing costs, have been constantly adjusted in order to optimize the use of resources. We aimed to assess the impact of SARS-CoV-2 test costs and reimbursement tariff adjustments on diagnostic strategies in Switzerland to determine the advantages and disadvantages of different costs and resource saving plans. We specifically assessed the cost of diagnostic SARS-COV-2 RT-PCR using five different approaches: i) in-house platform, ii) cobas 6800® (Roche, Basel, Switzerland), iii) GeneXpert® SARS-CoV-2 test (Cepheid, Sunnyvale, CA, USA), iv) VIASURE SARS-CoV-2 (N1 + N2) Real-Time PCR Detection Kit for BD MAX™ (Becton Dickinson, Franklin Lake, NJ, USA), v) cobas® Liat® SARS-CoV-2 & Influenza A/B (Roche, Basel, Switzerland). We compared these costs to the evolution of the reimbursement tariffs. The cost of a single RT-PCR test varied greatly (as did the volume of tests performed), ranging from as high as 180 CHF per test at the beginning of the pandemic (February to April 2020) to as low as 82 CHF per test at the end of 2020. Depending on the time period within the pandemic, higher costs did not necessarily mean greater benefits for the laboratories. The costs of molecular reagents for rapid tests were higher than of those for classic RT-PCR platforms, but the rapid tests had reduced turnaround times (TATs), thus improving patient care and enabling more efficient implementation of isolation measures, as well as reducing the burden of possible nosocomial infections. At the same time, there were periods when the production or distribution of these reagents was insufficient, and only the use of several different molecular platforms allowed us to sustain the high number of tests requested. Cost-saving plans need to be thoroughly assessed and constantly adjusted according to the epidemiological situation, the clinical context and the national resources in order to always guarantee that the highest performing diagnostic solutions are available. Not all cost-saving strategies guarantee good analytical performance

Viral load of SARS-CoV-2 across patients and compared to other respiratory viruses.

RT-PCRs to detect SARS-CoV-2 RNA is key to manage the COVID-19 pandemic. We analyzed SARS-CoV-2 viral loads from 22'323 RT-PCR results according to samples types, gender, age, and health units. Viral load did not show any difference across age and appears to be a poor predictor of disease outcome. SARS-CoV-2 viral load showed similar high viral loads than the one observed for RSV and influenza B. The importance of viral load to predict contagiousness and to assess disease progression is discussed

Impact of different SARS-CoV-2 assays on laboratory turnaround time.

Introduction. Clinical microbiology laboratories have had to cope with an increase in the volume of tests due to the emergence of the SARS-CoV-2 virus. Short turnaround times (TATs) are important for case tracing and to help clinicians in patient management. In such a context, high-throughput systems are essential to process the bulk of the tests. Rapid tests are also required to ensure shorter TATs for urgent situations. In our laboratory, SARS-CoV-2 assays were initially implemented on our custom platform using a previously published method. The commercial cobas 6800 (Roche diagnostics) assay and the GeneXpert Xpress (Cepheid) SARS-CoV-2 assay were implemented on 24 March and 8 April 2020, respectively, as soon as available.Hypothesis/Gap Statement. Despite the abundant literature on SARS-CoV-2 assays, the articles focus mainly on the diagnostic performances. This is to our knowledge the first article that specifically studies the TAT of different assays.Aim. We aimed to describe the impact of various SARS-CoV-2 assays on the TAT at the beginning of the outbreak.Methodology. In this study, we retrospectively analysed the TAT of all SARS-CoV-2 assays performed in our centre between 24 February and 9 June, 2020.Results. We retrieved 33 900 analyses, with a median TAT of 6.25 h. TATs were highest (6.9 h) when only our custom platform was used (24 February to 24 March, 2020). They were reduced to 6.1 h when the cobas system was introduced (24 March to 8 April, 2020). The implementation of the GeneXpert further reduced the median TAT to 4.8 h (8 April to 9 June, 2020). The GeneXpert system had the shortest median TAT (1.9 h), followed by the cobas (5.5 h) and by our custom platform (6.9 h).Conclusion. This work shows that the combination of high-throughput systems and rapid tests allows the efficient processing of a large number of tests with a short TAT. In addition, the use of a custom platform allowed the quick implementation of an in-house test when commercial assays were not yet available

Révolution dans le monde de la Tuberculose

Cette étude a démontré la possibilité d'utiliser le GeneXpert MTB/RIF, non seulement pour le diagnostic initial de la tuberculose, mais surtout pour évaluer le potentiel de transmission de la maladie des patients tuberculeux. Elle a permis d’introduire pour la première fois un algorithme clinique et microbiologique de prise en charge des patients avec suspicion de tuberculose dans lequel le GeneXpert remplace la détection de BAAR par examen direct pour initier le dia-gnostique microbiologique. Ce changement diagnostique, qui sonne comme une révolution dans le monde de la tuberculose, est une valeur ajoutée indéniable en termes de gestion de flux de patients, de leur prise en charge clinique et de l’organisation du laboratoire de microbiologie

Genome of the carbapenemase-producing clinical isolate Elizabethkingia miricola EM_CHUV and comparative genomics with Elizabethkingia meningoseptica and Elizabethkingia anophelis: evidence for intrinsic multidrug resistance trait of emerging pathogens.

Elizabethkingia miricola is a Gram-negative non-fermenting rod emerging as a life-threatening human pathogen. The multidrug-resistant (MDR) carbapenemase-producing clinical isolate E. miricola EM_CHUV was recovered in the setting of severe nosocomial pneumonia. In this study, the genome of E. miricola EM_CHUV was sequenced and a functional analysis was performed, including a comparative genomic study with Elizabethkingia meningoseptica and Elizabethkingia anophelis. The resistome of EM_CHUV revealed the presence of a high number of resistance genes, including the presence of the blaGOB-13 and blaB-9 carbapenemase-encoding genes. Twelve mobility genes, with only two of them located in the proximity of resistance genes, and four potential genomic islands were identified in the genome of EM_CHUV, but no prophages or CRISPR sequences. Ten restriction-modification system (RMS) genes were also identified. In addition, we report the presence of a putative conjugative plasmid (pEM_CHUV) that does not encode any antibiotic resistance genes. Altogether, these findings point towards a limited number of DNA exchanges with other bacteria and suggest that multidrug resistance is an intrinsic trait of E. miricola owing to the presence of a high number of resistance genes within the bacterial core genome

Detection of respiratory bacterial pathogens causing atypical pneumonia by multiplex Lightmix^® RT-PCR.

Pneumonia is a severe infectious disease. In addition to common viruses and bacterial pathogens (e.g. Streptococcus pneumoniae), fastidious respiratory pathogens like Chlamydia pneumoniae, Mycoplasma pneumoniae and Legionella spp. can cause severe atypical pneumonia. They do not respond to penicillin derivatives, which may cause failure of antibiotic empirical therapy. The same applies for infections with B. pertussis and B. parapertussis, the cause of pertussis disease, that may present atypically and need to be treated with macrolides. Moreover, these fastidious bacteria are difficult to identify by culture or serology, and therefore often remain undetected. Thus, rapid and accurate identification of bacterial pathogens causing atypical pneumonia is crucial. We performed a retrospective method evaluation study to evaluate the diagnostic performance of the new, commercially available Lightmix <sup>®</sup> multiplex RT-PCR assay that detects these fastidious bacterial pathogens causing atypical pneumonia. In this retrospective study, 368 clinical respiratory specimens, obtained from patients suffering from atypical pneumonia that have been tested negative for the presence of common agents of pneumonia by culture and viral PCR, were investigated. These clinical specimens have been previously characterized by singleplex RT-PCR assays in our diagnostic laboratory and were used to evaluate the diagnostic performance of the respiratory multiplex Lightmix <sup>®</sup> RT-PCR. The multiplex RT-PCR displayed a limit of detection between 5 and 10 DNA copies for different in-panel organisms and showed identical performance characteristics with respect to specificity and sensitivity as in-house singleplex RT-PCRs for pathogen detection. The Lightmix <sup>®</sup> multiplex RT-PCR assay represents a low-cost, time-saving and accurate diagnostic tool with high throughput potential. The time-to-result using an automated DNA extraction device for respiratory specimens followed by multiplex RT-PCR detection was below 4 h, which is expected to significantly improve diagnostics for atypical pneumonia-associated bacterial pathogens