Point-of-care laboratory testing in primary care: utilization, limitations and perspectives of general practitioners in Germany.

BACKGROUND: Due to their fast turnaround time and user-friendliness, point-of-care tests (POCTs) possess a great potential in primary care. The purpose of the study was to assess general practitioners' (GPs) perspectives on POCT use in German primary care, including utilization, limitations and requirements. METHODS: We conducted a cross-sectional survey study among GPs in Germany (federal states of Thuringia, Bremen and Bavaria (Lower Franconia), study period: 04/22-06/2022). RESULTS: From 2,014 GPs reached, 292 participated in our study (response rate: 14.5%). The median number of POCTs used per GP was 7.0 (IQR: 5.0-8.0). Six POCTs are used by the majority of surveyed GPs (> 50%): urine dipstick tests (99%), glucose (urine [91%] and plasma [69%]), SARS-CoV-2 (80%), urine microalbumin (77%), troponin I/T (74%) and prothrombin time / international normalized ratio (65%). The number of utilized POCTs did not differ between GP practice type (p = 0.307) and population size of GP practice location (p = 0.099). The great majority of participating German GPs (93%) rated POCTs as useful diagnostic tools in the GP practice. GPs ranked immediate decisions on patient management and the increase in diagnostic certainty as the most important reasons for performing POCTs. The most frequently reported limitations of POCT use in the GP practice were economic aspects (high costs and inadequate reimbursement), concerns regarding diagnostic accuracy, and difficulties to integrate POCT-testing into practice routines (e.g. time and personnel expenses). CONCLUSION: Although participating German GPs generally perceive POCTs as useful diagnostic tools and numerous POCTs are available, several test-related and contextual factors contribute to the relatively low utilization of POCTs in primary care.

Evaluation of Four Strategies for SARS-CoV-2 Detection: Characteristics and Prospects.

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed an enormous burden on the global public health system and has had disastrous socioeconomic consequences. Currently, single sampling tests, 20-in-1 pooling tests, nucleic acid point-of-care tests (POCTs), and rapid antigen tests are implemented in different scenarios to detect SARS-CoV-2, but a comprehensive evaluation of them is scarce and remains to be explored. In this study, 3 SARS-CoV-2 inactivated cell culture supernatants were used to evaluate the analytical performance of these strategies. Additionally, 5 recombinant SARS-CoV-2 nucleocapsid (N) proteins were also used for rapid antigen tests. For the wild-type (WT), Delta, and Omicron strains, the lowest inactivated virus concentrations to achieve 100% detection rates of single sampling tests ranged between 1.28 × 102 to 1.02 × 103, 1.28 × 102 to 4.10 × 103, and 1.28 × 102 to 2.05 × 103 copies/mL. The 20-in-1 pooling tests ranged between 1.30 × 102 to 1.04 × 103, 5.19 × 102 to 2.07 × 103, and 2.59 × 102 to 1.04 × 103 copies/mL. The nucleic acid POCTs were all 1.42 × 103 copies/mL. The rapid antigen tests ranged between 2.84 × 105 to 7.14 × 106, 8.68 × 104 to 7.14 × 106, and 1.12 × 105 to 3.57 × 106 copies/mL. For the WT, Delta AY.2, Delta AY.1/AY.3, Omicron BA.1, and Omicron BA.2 recombinant N proteins, the lowest concentrations to achieve 100% detection rates of rapid antigen tests ranged between 3.47 to 142.86, 1.74 to 142.86, 3.47 to 142.86, 3.47 to 142.86, and 5.68-142.86 ng/mL, respectively. This study provided helpful insights into the scientific deployment of tests and recommended the full-scale consideration of the testing purpose, resource availability, cost performance, result rapidity, and accuracy to facilitate a profound pathway toward the long-term surveillance of coronavirus disease 2019 (COVID-19). IMPORTANCE In the study, we reported an evaluation of 4 detection strategies implemented in different scenarios for SARS-CoV-2 detection: single sampling tests, 20-in-1 pooling tests, nucleic acid point-of-care tests, and rapid antigen tests. 3 SARS-CoV-2-inactivated SARS-CoV-2 cell culture supernatants and 5 recombinant SARS-CoV-2 nucleocapsid proteins were used for evaluation. In this analysis, we found that for the WT, Delta, and Omicron supernatants, the lowest concentrations to achieve 100% detection rates of single sampling tests ranged between 1.28 × 102 to 1.02 × 103, 1.28 × 102 to 4.10 × 103, and 1.28 × 102 to 2.05 × 103 copies/mL. The 20-in-1 pooling tests ranged between 1.30 × 102 to 1.04 × 103, 5.19 × 102 to 2.07 × 103, and 2.59 × 102 to 1.04 × 103 copies/mL. The nucleic acid POCTs were all 1.42 × 103 copies/mL. The rapid antigen tests ranged between 2.84 × 105 to 7.14 × 106, 8.68 × 104 to 7.14 × 106, and 1.12 × 105 to 3.57 × 106 copies/mL. For the WT, Delta AY.2, Delta AY.1/AY.3, Omicron BA.1, and Omicron BA.2 recombinant N proteins, the lowest concentrations to achieve 100% detection rates of rapid antigen tests ranged between 3.47 to 142.86, 1.74 to 142.86, 3.47 to 142.86, 3.47 to 142.86, and 5.68 to 142.86 ng/mL, respectively.

Merging microfluidics with luminescence immunoassays for urgent point-of-care diagnostics of COVID-19.

The Coronavirus disease 2019 (COVID-19) outbreak has urged the establishment of a global-wide rapid diagnostic system. Current widely-used tests for COVID-19 include nucleic acid assays, immunoassays, and radiological imaging. Immunoassays play an irreplaceable role in rapidly diagnosing COVID-19 and monitoring the patients for the assessment of their severity, risks of the immune storm, and prediction of treatment outcomes. Despite of the enormous needs for immunoassays, the widespread use of traditional immunoassay platforms is still limited by high cost and low automation, which are currently not suitable for point-of-care tests (POCTs). Microfluidic chips with the features of low consumption, high throughput, and integration, provide the potential to enable immunoassays for POCTs, especially in remote areas. Meanwhile, luminescence detection can be merged with immunoassays on microfluidic platforms for their good performance in quantification, sensitivity, and specificity. This review introduces both homogenous and heterogenous luminescence immunoassays with various microfluidic platforms. We also summarize the strengths and weaknesses of the categorized methods, highlighting their recent typical progress. Additionally, different microfluidic platforms are described for comparison. The latest advances in combining luminescence immunoassays with microfluidic platforms for POCTs of COVID-19 are further explained with antigens, antibodies, and related cytokines. Finally, challenges and future perspectives were discussed.

Sensing and 3D printing technologies in personalized healthcare for the management of health crises including the COVID-19 outbreak.

A major threat that has surrounded human civilization since the beginning of the year 2020 is the outbreak of coronavirus disease 2019 (COVID-19). It has been declared a pandemic by the World Health Organization and significantly affected populations globally, causing medical and economic despair. Healthcare chains across the globe have been under grave stress owing to shortages of medical equipments necessary to address a pandemic. Furthermore, personal protective equipment supplies, mandatory for healthcare staff for treating severely ill patients, have been in short supply. To address the necessary requisites during the pandemic, several researchers, hospitals, and industries collaborated to meet the demand for these medical equipments in an economically viable manner. In this context, 3D printing technologies have provided enormous potential in creating personalized healthcare equipment, including face masks, face shields, rapid detection kits, testing swabs, biosensors, and various ventilator components. This has been made possible by capitalizing on centralized large-scale manufacturing using 3D printing and local distribution of verified and tested computer-aided design files. The primary focus of this study is, "How 3D printing is helpful in developing these equipments, and how it can be helpful in the development and deployment of various sensing and point-of-care-testing (POCTs) devices for the commercialization?" Further, the present study also takes care of patient safety by implementing novel 3D printed health equipment used for COVID-19 patients. Moreover, the study helps identify and highlight the efforts made by various organizations toward the usage of 3D printing technologies, which are helpful in combating the ongoing pandemic.

SARS-CoV-2 Diagnostics Based on Nucleic Acids Amplification: From Fundamental Concepts to Applications and Beyond.

COVID-19 pandemic ignited the development of countless molecular methods for the diagnosis of SARS-CoV-2 based either on nucleic acid, or protein analysis, with the first establishing as the most used for routine diagnosis. The methods trusted for day to day analysis of nucleic acids rely on amplification, in order to enable specific SARS-CoV-2 RNA detection. This review aims to compile the state-of-the-art in the field of nucleic acid amplification tests (NAATs) used for SARS-CoV-2 detection, either at the clinic level, or at the Point-Of-Care (POC), thus focusing on isothermal and non-isothermal amplification-based diagnostics, while looking carefully at the concerning virology aspects, steps and instruments a test can involve. Following a theme contextualization in introduction, topics about fundamental knowledge on underlying virology aspects, collection and processing of clinical samples pave the way for a detailed assessment of the amplification and detection technologies. In order to address such themes, nucleic acid amplification methods, the different types of molecular reactions used for DNA detection, as well as the instruments requested for executing such routes of analysis are discussed in the subsequent sections. The benchmark of paradigmatic commercial tests further contributes toward discussion, building on technical aspects addressed in the previous sections and other additional information supplied in that part. The last lines are reserved for looking ahead to the future of NAATs and its importance in tackling this pandemic and other identical upcoming challenges.