Appropriate Use and Future Directions of Molecular Diagnostic Testing

Magnetically localized and wash-free fluorescent immuno-assay: From a research platform (MLFIA) to a multiplexed POC system (MagIA)

Sexually transmitted infections (STI) remain one of the world's public health priorities: Nearly 400 million people are infected not only in emerging, but also in western countries. HIV, HBV and HCV share common infection pathways; thus these 3 diseases are recommended to be tested at the same time. However, this combined approach is currently mainly available in laboratories, and seldomly at the Point-of-care (POC). Consequently, there is a need for a STI screening POC platform with laboratory-like performance. Such a platform should be autonomous and portable and enable multiplexed screening from capillary blood. The previously developed and introduced MLFIA (Magnetically Localized and wash-free Fluorescent Immuno-Assay) technology has the potential to address these needs, as the MLFIA 18-chamber microfluidic cartridge and the MLFIA Analyzer were previously characterized and evaluated with plasma and serum from patients infected with HIV, Hepatitis B (Hep B) or C (Hep C). Here, we present the efforts to transfer this research platform (MLFIA) to a fully integrated multi-analysis solution (MagIA). First, we present the design changes of the consumable enabling to perform multiple assays in parallel, a fast filling of the cartridge with patient samples, and a homogeneous reagent/sample incubation. Second, we describe the development a piezoelectric actuator integrated into the Analyzer: this mixing module allows for an automated, fully integrated and portable workflow, with homogeneous in-situ mixing capabilities. The obtained MagIA platform was further characterized and validated for immunoassays (LOD, cartridge stability over time), using various biological models including OVA and IgG. We discuss the performances of the MLFIA and MagIA platforms for the detection of HIV / Hep B / Hep C using results from 102 patient plasma samples. Lastly, we assessed the compatibility of the MagIA platform with veinous and capillary blood samples as a final step towards its POC validation.

Molecular Pathology Education: A Suggested Framework for Primary Care Resident Training in Genomic Medicine: A Report of the Association for Molecular Pathology Training and Education Committee

Developments in genomics are profoundly influencing medical practice. With increasing use of genetic and genomic testing across every aspect of the health care continuum, patients and their families are increasingly turning to primary care physicians (PCPs) for discussion and advice regarding tests, implications, and results. Yet, with the rapid growth of information, technology, and applications, PCPs are finding it challenging to fill the gaps in knowledge and support the growing needs of their patients. A critical component in expanding PCP genomic literacy lies in the education of physicians in training and in practice. Although a framework for developing physician competencies in genomics has already been developed, the Association for Molecular Pathology is uniquely situated to actively utilize the skills of its members to engage and support PCPs in this effort. This report provides an overview and a suggested basic teaching framework, which can be used by molecular professionals in their individual institutions as a starting point for educational outreach.

Faster infection diagnostics for intensive care unit (ICU) patients

INTRODUCTION

: The patient admitted to intensive care units (ICU) is critically ill, to some extent immunosuppressed, with a high risk of infection, sometimes by multidrug-resistant microorganisms. In this context, the intensivist expects from the microbiology service quick and understandable information so that appropriate antimicrobial treatment for that particular patient and infection can be initiated.

AREAS COVERED

: In this review of recent literature (2015-2021), we identified diagnostic methods for the most prevalent infections in these patients through a search of the databases Pubmed, evidence-based medicine online, York University reviewers group, Cochrane, MBE-Trip, and Sumsearch using the terms: adult, clinical laboratory techniques, critical care, early diagnosis, microbiology, molecular diagnostic techniques, spectrometry and metagenomics.

EXPERT OPINION

: There has been an exponential surge in diagnostic systems used directly on blood and other samples to expedite microbial identification and antimicrobial susceptibility testing of pathogens. Few studies have thus far assessed their clinical impact; final outcomes will also depend on preanalytical and post-analytical factors. Besides, many of the resistance mechanisms cannot yet be detected with molecular techniques, which impairs the prediction of the actual resistance phenotype.

Nonetheless, this is an exciting field with much yet to explore.

Provider views on rapid diagnostic tests and antibiotic prescribing for respiratory tract infections: A mixed methods study

BACKGROUND

Respiratory tract infections (RTIs) are often inappropriately treated with antibiotics. Rapid diagnostic tests (RDTs) have been developed with the aim of improving antibiotic prescribing but uptake remains low. The aim of this study was to examine provider knowledge, attitudes and behaviors regarding RDT use and their relationship to antibiotic prescribing decisions across multiple clinical departments in an urban safety-net hospital.

METHODS

We conducted a mixed methods sequential explanatory study. Providers with prescribing authority (attending physicians, nurse practitioners and physician assistants) who had at least 20 RTI encounters from January 1, 2016 to December 31, 2018. Eighty-five providers completed surveys and 16 participated in interviews. We conducted electronic surveys via RedCap from April to July 2019, followed by semi-structured individual interviews from October to December 2019, to ascertain knowledge, attitudes and behaviors related to RDT use and antibiotic prescribing.

RESULTS

Survey findings indicated that providers felt knowledgeable about antibiotic prescribing guidelines. They reported high familiarity with the rapid streptococcus and rapid influenza tests. Familiarity with comprehensive respiratory panel PCR (RPP-respiratory panel PCR) and procalcitonin differed by clinical department. Qualitative interviews identified four main themes: providers trust their clinical judgment more than rapid test results; patient-provider relationships play an important role in prescribing decisions; there is patient demand for antibiotics and providers employ different strategies to address the demand and providers do not believe RDTs are implemented with sufficient education or evidence for clinical practice.

CONCLUSION

Prescribers are knowledgeable about prescribing guidelines but often rely on clinical judgement to make final decisions. The utility of RDTs is specific to the type of RDT and the clinical department. Given the low familiarity and clinical utility of RPP and procalcitonin, providers may require additional education and these tests may need to be implemented differently based on clinical department.

Future potential of metagenomics in clinical laboratories

INTRODUCTION

Rapid and sensitive diagnostic strategies are necessary for patient care and public health. Most of the current conventional microbiological assays detect only a restricted panel of pathogens at a time or require a microbe to be successfully cultured from a sample. Clinical metagenomics next-generation sequencing (mNGS) has the potential to unbiasedly detect all pathogens in a sample, increasing the sensitivity for detection and enabling the discovery of unknown infectious agents.

AREAS COVERED

High expectations have been built around mNGS; however, this technique is far from widely available. This review highlights the advances and currently available options in terms of costs, turnaround time, sensitivity, specificity, validation, and reproducibility of mNGS as a diagnostic tool in clinical microbiology laboratories.

EXPERT OPINION

The need for a novel diagnostic tool to increase the sensitivity of microbial diagnostics is clear. mNGS has the potential to revolutionise clinical microbiology. However, its role as a diagnostic tool has yet to be widely established, which is crucial for successfully implementing the technique. A clear definition of diagnostic algorithms that include mNGS is vital to show clinical utility. Similarly to real-time PCR, mNGS will one day become a vital tool in any testing algorithm.

Syndromic diagnostic testing: a new way to approach patient care in the treatment of infectious diseases

Advanced microbiology technologies such as multiplex molecular assays (i.e. syndromic diagnostic tests) are a novel approach to the rapid diagnosis of common infectious diseases. As the global burden of antimicrobial resistance continues to rise, the judicious use of antimicrobials is of utmost importance. Syndromic panels are now being recognized in some clinical practice guidelines as a 'game-changer' in the diagnosis of infectious diseases. These syndromic panels, if implemented thoughtfully and interpreted carefully, have the potential to improve patient outcomes through improved clinical decision making, optimized laboratory workflow, and enhanced antimicrobial stewardship. This paper reviews the potential benefits of and considerations regarding various infectious diseases syndromic panels, and highlights how to maximize impact through collaboration between clinical microbiology laboratory and antimicrobial stewardship programmes.

The Need for Dedicated Microbiology Leadership in the Clinical Microbiology Laboratory

Clinical microbiology laboratories play a crucial role in patient care using traditional and innovative diagnostics. Challenges faced by laboratories include emerging pathogens, rapidly evolving technologies, health care-acquired infections, antibiotic-resistant organisms, and diverse patient populations. Despite these challenges, many clinical microbiology laboratories in the United States are not directed by doctoral level microbiology-trained individuals with sufficient time dedicated to laboratory leadership. The manuscript highlights the need for medical microbiology laboratory directors with appropriate training and qualifications.

Diagnostic stewardship based on patient profiles: differential approaches in acute versus chronic infectious syndromes

Introduction: New diagnostics may be useful in clinical practice, especially in contexts of high prevalence of multidrug-resistant organisms (MDRO). However, misuse of diagnostic tools may lead to increased costs and worse patient outcome. Conventional and new techniques should be appropriately positioned in diagnostic algorithms to guide an appropriate use of antimicrobial therapy.Areas covered: A panel of experts identified 4 main areas in which the implementation of diagnostic stewardship is needed. Among chronic infections, bone and prosthetic joint infections and subacute-chronic intravascular infections and endocarditis represent common challenges for clinicians. Among acute infections, bloodstream infections and community-acquired pneumonia may be associated with high mortality and require appropriate diagnostic approach.Expert opinion: Diagnostic stewardship aims to improve the appropriate use of microbiological diagnostics to guide therapeutic decisions through appropriate and timely diagnostic testing. Here, diagnostic algorithms based on different patient profiles are proposed for chronic and acute clinical syndromes. In each clinical scenario, combining conventional and new diagnostic techniques is crucial to make a rapid and accurate diagnosis and to guide the selection of antimicrobial therapy. Barriers related to the implementation of new rapid diagnostic tools, such as high initial costs, may be overcome through their rational and structured use.

Implementation of infectious diseases rapid molecular diagnostic tests and antimicrobial stewardship program involvement in acute-care hospitals

A survey of acute-care hospitals found that rapid molecular diagnostic tests (RMDTs) have been widely adopted. Although many hospitals use their antimicrobial stewardship team and/or guidelines to help clinicians interpret results and optimize treatment, opportunities to more fully achieve the potential benefits of RMDTs remain.

Drug-Resistant Fungi: An Emerging Challenge Threatening Our Limited Antifungal Armamentarium

The high clinical mortality and economic burden posed by invasive fungal infections (IFIs), along with significant agricultural crop loss caused by various fungal species, has resulted in the widespread use of antifungal agents. Selective drug pressure, fungal attributes, and host- and drug-related factors have counteracted the efficacy of the limited systemic antifungal drugs and changed the epidemiological landscape of IFIs. Species belonging to Candida, Aspergillus, Cryptococcus, and Pneumocystis are among the fungal pathogens showing notable rates of antifungal resistance. Drug-resistant fungi from the environment are increasingly identified in clinical settings. Furthermore, we have a limited understanding of drug class-specific resistance mechanisms in emerging Candida species. The establishment of antifungal stewardship programs in both clinical and agricultural fields and the inclusion of species identification, antifungal susceptibility testing, and therapeutic drug monitoring practices in the clinic can minimize the emergence of drug-resistant fungi. New antifungal drugs featuring promising therapeutic profiles have great promise to treat drug-resistant fungi in the clinical setting. Mitigating antifungal tolerance, a prelude to the emergence of resistance, also requires the development of effective and fungal-specific adjuvants to be used in combination with systemic antifungals.

Recommendations for the Diagnosis, Prevention, and Control of Coronavirus Disease-19 in Children-The Chinese Perspectives

Ever since SARS-CoV-2 began infecting people by the end of 2019, of whom some developed severe pneumonia (about 5%), which could be fatal (case fatality ~3.5%), the extent and speed of the COVID-19 outbreak has been phenomenal. Within 2.5 months (by March 18, 2020) over 191,127 COVID-19 patients have been identified in 161 countries. By then, over 700 pediatric patients were confirmed to have COVID-19 in China, with only about 58 diagnosed elsewhere. By now, there are thousands of children and adolescents infected. Chinese pediatricians would like to share their experience on how these patients were managed in China and the key recommendations that had guided them in meeting the evolving challenges. A group of experts were summoned by the Chinese Pediatric Society and Editorial Board of Chinese Journal of Pediatrics to extract informative data from a survey on confirmed COVID-19 pediatric patients in China. Consensus on diagnosis, management, and prevention of pediatric COVID-19 were drawn up based on the analysis of such data plus insights gained from the past SARS and MERS coronavirus outbreaks. Relevant cumulating experiences from physicians managing adult patients, expedited reports on clinical and scientific COVID-19 and SARS-CoV-2 data, and the National Health Committee guidelines on COVID-19 management were integrated into this proposal.