How point-of-care testing could drive innovation in global health

Towards the development of cost-effective point-of-care diagnostic tools for poverty-related infectious diseases in sub-Saharan Africa

In this review, we examine the current landscape of point-of-care testing (POCT) diagnostic tools designed for poverty-related infectious diseases (PRIDs) in sub-Saharan Africa (sSA) while delineating key avenues for future advancements. Our analysis encompasses both established and emerging diagnostic methods for PRIDs, addressing the persistent challenges in POCT tool development and deployment, such as cost, accessibility, and reliability. We emphasize recent advancements in POCT diagnostic tools as well as platforms poised to enhance diagnostic testing in sSA. Recognizing the urgency for affordable and widely accessible POCT diagnostic tools to detect PRIDs in sSA, we advocate for a multidisciplinary approach. This approach integrates current and emerging diagnostic methods, explicitly addressing challenges hindering point-of-care (POC) tool development. Furthermore, it recognizes the profound impact of misdiagnosis on public and global health, emphasizing the need for effective tools. To facilitate the successful development and implementation of POCT diagnostic tools in sSA, we propose strategies including the creation of multi-analyte detection POCT tools, the implementation of education and training programs, community engagement initiatives, fostering public-private collaborations, and the establishment of reliable supply chains. Through these concerted efforts, we aim to accelerate the development of POCT in the sSA region, ensuring its effectiveness and accessibility in addressing the diagnostic challenges associated with PRIDs.

Miniature mass spectrometer-based point-of-care assay for quantification of metformin and sitagliptin in human blood and urine

Metformin (MET) and sitagliptin (STG) are widely used as the first-line and long-term oral hypoglycemic agents for managing type 2 diabetes mellitus (T2DM). However, the current lack of convenient and rapid measurement methods poses a challenge for individualized management. This study developed a point-of-care (POC) assay method utilizing a miniature mass spectrometer, enabling rapid and accurate quantification of MET and STG concentrations in human blood and urine. By combining the miniature mass spectrometer with paper spray ionization, this method simplifies the process into three to four steps, requires minimal amounts of bodily fluids (50 μL of blood and 2 μL of urine), and is able to obtain quantification results within approximately 2 min. Stable isotope-labeled internal standards were employed to enhance the accuracy and stability of measurement. The MS/MS responses exhibited good linear relationship with concentration, with relative standard deviations (RSDs) below 25%. It has the potential to provide immediate treatment feedback and decision support for patients and healthcare professionals in clinical practice.

Sample-to-result molecular diagnostic platforms and their suitability for infectious disease testing in low- and middle-income countries

INTRODUCTION

Diagnostics are an essential, undervalued part of the health-care system. For many diseases, molecular diagnostics are the gold standard, but are not easy to implement in Low- and Middle-Income Countries (LMIC). Sample-to-result (S2R) platforms combining all procedures in a closed system could offer a solution. In this paper, we investigated their suitability for implementation in LMIC.

AREAS COVERED

A scorecard was used to evaluate different platforms on a range of parameters. Most platforms scored fairly on the platform itself, ease-of-use and test consumables; however, shortcomings were identified in cost, distribution and test panels tailored to LMIC needs. The diagnostic coverage for common infectious diseases was found to have a wider coverage in high-income countries (HIC) than LMIC. A literature study showed that in LMIC, these platforms are mainly used as diagnostic tools or evaluation of diagnostic performance, with a minority assessing the operational characteristics or the clinical utility. In this narrative review, we identified various points for adaptation of S2R platforms to LMIC conditions.

EXPERT OPINION

For S2R platforms to be suitable for implementation in LMIC some modifications by the manufacturers could be considered. Furthermore, strengthening health systems and digitalization are vital; as are smaller, cheaper, faster, and sustainable technologies.

Analytical performance specifications and quality assurance of point-of-care testing in primary healthcare

Point-of-care testing (POCT) is the fastest-growing segment of laboratory medicine. This review focuses on the essential aspects of setting analytical performance specifications (APS) and performing quality assurance for POCT in primary healthcare. In-vitro diagnostic medical devices for POCT are typically small and easy to operate. Users often have little to no laboratory experience and may not necessarily see the value of conducting quality assurance on their devices. Therefore, training, guidance, and motivation should be integral parts of the total quality management system, as they are vital for managing errors and ensuring reliable results. It is common to believe that the analytical quality of POCT should be comparable to that of laboratory testing, and as a result, APS should be the same. This paper challenges this concept. The APS for POCT can often be less stringent compared to those used in a central laboratory because the requester is closer to both the analytical and clinical situation. Point-of-care instruments should be selected based on clinical needs, the required analytical quality and user-friendliness in the intended usage setting.Quality assurance should include both internal quality control (IQC) and external quality assessment (EQA). It is recommended that IQC protocols should be dependent on the complexity of the POCT device. A scoring system to determine how frequent IQC should be analyzed in primary healthcare on different types of POCT devices has been suggested. The main challenge in EQA for POCT involves using suitable control materials that reflect instrument performance on patient samples. Obtaining commutable control materials for POCT is difficult since the matrix often is whole blood. An essential aspect of EQA for POCT is that feedback reports should be easily interpretable. Users should receive advice from the EQA organizer regarding the root causes of deviating results. Quality assurance for POCT is not an easy task and presents numerous challenges. However, there is evidence that quality assurance improves the quality of POCT measurements and, consequently, can enhance patient outcomes.

Analyzing SDG interlinkages: identifying trade-offs and synergies for a responsible innovation

This paper responds to recent calls to address the indivisible nature of the Sustainable Development Goal (SDG) framework and the related knowledge gap on how SDG targets interlink with each other. It examines how SDG targets interact in the context of a specific technology, point of care (PoC) microfluidics, and how this relates to the concept of responsible innovation (RI). The novel SDG interlinkages methodology developed here involves several steps to filter the relevant interlinkages and a focus group of experts for discussing these interlinkages. The main findings indicate that several social synergies occur when deploying PoC microfluidics, but that the environmental trade-offs may jeopardize the total progress toward the SDGs. More specifically, the environmental sacrifices (use of plastics and lack of recyclability) resulted in the product being cheaper and, thus, better accessible. This work suggests that attention should be given (and prioritized) to the use of renewable and recyclable materials without jeopardizing the accessibility of the product. This should minimize the identified trade-offs. These findings inform how analyzing SDG interlinkages relates to the responsibilities and dimensions of RI in several ways. First, analyzing SDG interlinkages helps to execute the governance responsibility by using the RI dimensions (anticipation, reflexivity, inclusion and responsiveness). Second, analyzing SDG interlinkages gives insights into if and how a technology relates to the do-good and avoid-harm responsibility. This is important to assess the responsiveness of the technology to ensure that the technology can become truly sustainable and leaves no one behind.

Point-of-Care Testing in Chronic Kidney Disease of Non-Traditional Origin: Considerations for Clinical, Epidemiological, and Health Surveillance Research and Practice

Purpose

As the prevalence of chronic kidney disease of non-traditional origin (CKDnt) rises in low-resource settings, there is a need for reliable point-of-care creatinine testing. The purpose of this analysis was to assess the accuracy of two commonly used point-of-care creatinine devices, the i-STAT handheld (Abbott, Princeton, NJ, USA) and the StatSensor Creatinine (Nova Biomedical, Waltham, MA, USA) in comparison to venipuncture serum creatinine measures. The affordability, sensitivity, specificity, ease of use, and other considerations for each device are also presented.

Methods

Three paired data sets were compared. We collected 213 paired i-STAT and venipuncture samples from a community study in Nicaragua in 2015-2016. We also collected 267 paired StatSensor Creatinine and venipuncture samples, including 158 from a community setting in Nicaragua in 2014-2015 and 109 from a Guatemala sugarcane worker cohort in 2017-2018. Pearson correlation coefficients, Bland-Altman plots, and no intercept linear regression models were used to assess agreement between point-of-care devices and blood samples.

Results

The i-STAT performed the most accurately, overestimating creatinine by 0.07 mg/dL (95% CI: 0.02, 0.12) with no evidence of proportional bias. The StatSensor Creatinine performed well at low levels of creatinine (Mean (SD): 0.87 (0.19)). Due to proportional bias, the StatSensor Creatinine performed worse in the Nicaragua community setting where creatinine values ranged from 0.31 to 7.04 mg/dL.

Discussion

Both devices provide acceptable sensitivity and specificity. Although adequate for routine surveillance, StatSensor Creatinine is less accurate as the values of measured creatinine increase, a consideration when using the point-of-care device for screening individuals at risk for CKDnt. Research, clinical, and screening objectives, cost, ease of use, and background prevalence of disease must all be carefully considered when selecting a point-of-care creatinine device.

Conclusion

POC testing can be more accessible in resource-limited settings. The selection of the appropriate device will depend on the use-case.

LAMP-enabled diagnosis of Kaposi's sarcoma for sub-Saharan Africa

Kaposi's sarcoma (KS) is an endothelial cancer caused by the Kaposi's sarcoma-associated herpesvirus (KSHV) and is one of the most common cancers in sub-Saharan Africa. In limited-resource settings, traditional pathology infrastructure is often insufficient for timely diagnosis, leading to frequent diagnoses at advanced-stage disease where survival is poor. In this study, we investigate molecular diagnosis of KS performed in a point-of-care device to circumvent the limited infrastructure for traditional diagnosis. Using 506 mucocutaneous biopsies collected from patients at three HIV clinics in Uganda, we achieved 97% sensitivity, 92% specificity, and 96% accuracy compared to gold standard U.S.-based pathology. The results presented in this manuscript show that LAMP-based quantification of KSHV DNA extracted from KS-suspected biopsies has the potential to serve as a successful diagnostic for the disease and that diagnosis may be accurately achieved using a point-of-care device, reducing the barriers to obtaining KS diagnosis while increasing diagnostic accuracy.

Review of Mn-Doped Semiconductor Nanocrystals for Time-Resolved Luminescence Biosensing/Imaging

Colloidal semiconductor nanocrystals (NCs) have been developed for decades and are widely applied in biosensing/imaging. However, their biosensing/imaging applications are mainly based on luminescence-intensity measurement, which suffers from autofluorescence in complex biological samples and thus limits the biosensing/imaging sensitivities. It is expected for these NCs to be further developed to gain luminescence features that can overcome sample autofluorescence. On the other hand, time-resolved luminescence measurement utilizing long-lived-luminescence probes is an efficient technique to eliminate short-lived autofluorescence of samples while recording time-resolved luminescence of the probes for signal measurement after pulsed excitation from a light source. Despite time-resolved measurement being very sensitive, the optical limitations of many of the current long-lived-luminescence probes cause time-resolved measurement to be generally performed in laboratories with bulky and costly instruments. In order to apply highly sensitive time-resolved measurement for in-field or point-of-care (POC) testing, it is essential to develop probes possessing high brightness, low-energy (visible-light) excitation, and long lifetimes of up to milliseconds. Such desired optical features can significantly simplify the design criteria of time-resolved measurement instruments and facilitate the development of low-cost, compact, sensitive instruments for in-field or POC testing. Mn-doped NCs have recently been in rapid development and provide a strategy to solve the challenges faced by both colloidal semiconductor NCs and time-resolved luminescence measurement. In this review, we outline the major achievements in the development of Mn-doped binary and multinary NCs, with emphasis on their synthesis approaches and luminescence mechanisms. Specifically, we demonstrate how researchers approached these obstacles to achieve the aforementioned desired optical properties on the basis of the progressive understanding of Mn emission mechanisms. Afterward, we review representative applications of Mn-doped NCs in time-resolved luminescence biosensing/imaging and present the potential of Mn-doped NCs in advancing time-resolved luminescence biosensing/imaging for in-field or POC testing.

How to Realize the Benefits of Point-of-Care Testing at the General Practice: A Comparison of Four High-Income Countries

BACKGROUND

In some countries, such as the Netherlands and Norway, point-of-care testing (POCT) is more widely implemented in general practice compared to countries such as England and Australia. To comprehend what is necessary to realize the benefits of POCT, regarding its integration in primary care, it would be beneficial to have an overview of the structure of healthcare operations and the transactions between stakeholders (also referred to as value networks). The aim of this paper is to identify the current value networks in place applying to POCT implementation at general practices in England, Australia, Norway and the Netherlands and to compare these networks in terms of seven previously published factors that support the successful implementation, sustainability and scale-up of innovations.

METHODS

The value networks were described based on formal guidelines and standards published by the respective governments, organizational bodies and affiliates. The value network of each country was validated by at least two relevant stakeholders from the respective country.

RESULTS

The analysis revealed that the biggest challenge for countries with low POCT uptake was the lack of effective communication between the several organizations involved with POCT as well as the high workload for general practitioners (GPs) aiming to implement POCT. It is observed that countries with a single national authority responsible for POCT have a better uptake as they can govern the task of POCT roll-out and management and reduce the workload for GPs by assisting with set-up, quality control, training and support.

CONCLUSION

Setting up a single national authority may be an effective step towards realizing the full benefits of POCT. Although it is possible for day-to-day operations to fall under the responsibility of the GP, this is only feasible if support and guidance are readily available to ensure that the workload associated with POCT is limited and as low as possible.

Miniature mass spectrometer-based point-of-care assay for cabotegravir and rilpivirine in whole blood

HIV prevention and treatment with injectable cabotegravir and/or rilpivirine administered once every 4 to 8 weeks is an attractive alternative to daily therapy. Prescribed dosage and drug concentrations in plasma are based on patient data collected in clinical trials, but actual patients are expected to exhibit more variability in drug concentrations, which is important to quantify. Here, we demonstrate the first quantitative point-of-care assay with a miniature mass spectrometer to assess these drug concentrations in whole blood. Quantitative performance is obtained using paper spray ionization in combination with tandem mass spectrometry (MS/MS) in the clinically relevant concentration range of both drugs. Limits of quantitation (LoQs) of cabotegravir and rilpivirine are measured to be 750 ng/mL and 20 ng/mL, respectively. The assay turnaround time is < 4 min, and strong linear relationships are established between MS/MS responses and concentration, with percentage of relative standard deviations (RSDs) that are <15% at concentrations above the LoQs. The speed, portability, low power consumption, and specificity offered by the miniature instrument should make it an appropriate platform for measuring drug concentrations in a walk-in clinic using small volumes of patient blood.

Portable and sensitive detection of non-glucose target by enzyme-encapsulated metal-organic-framework using personal glucose meter

Personal glucose meter (PGM) is one of the most commercially available POC (point-of-care) devices for monitoring the level of glucose reliably, yet its non-glucose quantification ability is limited since such strategy needs ingenious interface design and tedious enzyme conjugation. Herein, we constructed a portable and sensitive platform that can detect non-glucose target by combining enzyme-encapsulated zeolitic imidazole framework-90 (ZIF-90) with personal glucose meter. ZIF-90 is an ideal carrier and susceptor due to the extraordinary capability of packaging enzyme and stimuli-responsiveness. We selected adenosine-5'-triphosphate (ATP) as the target model of non-glucose analytes. Upon ATP-induced decomposition of MOF, the released enzyme (glucose oxidase or invertase) catalyzed substrate and gave rise to the change of the glucose concentration for PGM assay. This method determined ATP with a remarkably sensitivity of 233 nM and effective recovery in real serum samples. Our strategy provides a facile and practical approach for measuring the non-glucose target using PGM, and could potentially be applied in bimolecular detection in point-of-care diagnosis.

Reagent Filming for Universal Point-of-Care Diagnostics

Simplifying assays while maintaining the robustness of reagents is a challenge in diagnostics. This problem is exacerbated when translating quality diagnostic assays to developing countries that lack resources and infrastructure such as trained health workers, high-end equipment, and cold-chain systems. To solve this problem, in this study, a simple solution that films assay reagents to simplify the operation of diagnostic assays and preserve the stability of diagnostic reagents without using cold chains is presented. A polyvinyl-alcohol-based water-soluble film is used to encapsulate premeasured and premixed reagents. The reagent film, produced through a simple and scalable cast-drying process, provides a glassy inner matrix with abundant hydroxyl groups that can stabilize various reagents (ranging from chemicals to biological materials) by restricting molecular mobility and generating hydrogen bonds. The reagent film is applied to an enzymatic glucose assay, a high-sensitivity immunoassay for cardiac troponin, and a molecular assay for viral RNA detection, to test its practicability and universal applicability. The film-based assays result in excellent analytical/diagnostic performance and stable long-term reagent storage at elevated temperatures (at 25 or 37 °C, for six months), demonstrating clinical readiness. This technology advances the development and distribution of affordable high-quality diagnostics to resource-limited regions.

Scaling up sexually transmissible infections point-of-care testing in remote Aboriginal and Torres Strait Islander communities: healthcare workers' perceptions of the barriers and facilitators

Background

Sexually transmissible infections (STIs), such as gonorrhoea and chlamydia, are highly prevalent, particularly in remote Aboriginal and Torres Strait Islander communities in Australia. In these settings, due to distance to centralised laboratories, the return of laboratory test results can take a week or longer, and many young people do not receive treatment, or it is considerably delayed. Point-of-care testing (POCT) provides an opportunity for same day diagnosis and treatment. Molecular POC testing for STIs was available at 31 regional or remote primary health care clinic sites through the Test-Treat-And-GO (TANGO2) program. This qualitative study sought to identify barriers and facilitators to further scaling up STI POCT in remote Aboriginal communities within Australia.

Methods

A total of 15 healthcare workers (including nurses and Aboriginal health practitioners) and five managers (including clinic coordinators and practice managers) were recruited from remote health services involved in the TTANGO2 program to participate in semi-structured in-depth interviews. Health services’ clinics were purposively selected to include those with high or low STI POCT uptake. Personnel participants were selected via a hybrid approach including nomination by clinic managers and purposive sampling to include those in roles relevant to STI testing and treatment and those who had received TTANGO2 training for POCT technology. Milat’s scaling up guide informed the coding framework and analysis.

Results

Acceptability of STI POCT technology among healthcare workers and managers was predominantly influenced by self-efficacy and perceived effectiveness of POCT technology as well as perceptions of additional workload burden associated with POCT. Barriers to integration of STI POCT included retention of trained staff to conduct POCT. Patient reach (including strategies for patient engagement) was broadly considered an enabler for STI testing scale up using POCT technology.

Conclusions

Remote healthcare clinics should be supported by both program and clinic management throughout scaling up efforts to ensure broad acceptability of STI POCT as well as addressing local health systems’ issues and identifying and enhancing opportunities for patient engagement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43058-021-00232-8.

Loop-Mediated Isothermal Amplification Detection of SARS-CoV-2 and Myriad Other Applications

As the second year of the COVID-19 pandemic begins, it remains clear that a massive increase in the ability to test for SARS-CoV-2 infections in a myriad of settings is critical to controlling the pandemic and to preparing for future outbreaks. The current gold standard for molecular diagnostics is the polymerase chain reaction (PCR), but the extraordinary and unmet demand for testing in a variety of environments means that both complementary and supplementary testing solutions are still needed. This review highlights the role that loop-mediated isothermal amplification (LAMP) has had in filling this global testing need, providing a faster and easier means of testing, and what it can do for future applications, pathogens, and the preparation for future outbreaks. This review describes the current state of the art for research of LAMP-based SARS-CoV-2 testing, as well as its implications for other pathogens and testing. The authors represent the global LAMP (gLAMP) Consortium, an international research collective, which has regularly met to share their experiences on LAMP deployment and best practices; sections are devoted to all aspects of LAMP testing, including preanalytic sample processing, target amplification, and amplicon detection, then the hardware and software required for deployment are discussed, and finally, a summary of the current regulatory landscape is provided. Included as well are a series of first-person accounts of LAMP method development and deployment. The final discussion section provides the reader with a distillation of the most validated testing methods and their paths to implementation. This review also aims to provide practical information and insight for a range of audiences: for a research audience, to help accelerate research through sharing of best practices; for an implementation audience, to help get testing up and running quickly; and for a public health, clinical, and policy audience, to help convey the breadth of the effect that LAMP methods have to offer.

Machine Learning-Reinforced Noninvasive Biosensors for Healthcare

The emergence and development of noninvasive biosensors largely facilitate the collection of physiological signals and the processing of health-related data. The utilization of appropriate machine learning algorithms improves the accuracy and efficiency of biosensors. Machine learning-reinforced biosensors are started to use in clinical practice, health monitoring, and food safety, bringing a digital revolution in healthcare. Herein, the recent advances in machine learning-reinforced noninvasive biosensors applied in healthcare are summarized. First, different types of noninvasive biosensors and physiological signals collected are categorized and summarized. Then machine learning algorithms adopted in subsequent data processing are introduced and their practical applications in biosensors are reviewed. Finally, the challenges faced by machine learning-reinforced biosensors are raised, including data privacy and adaptive learning capability, and their prospects in real-time monitoring, out-of-clinic diagnosis, and onsite food safety detection are proposed.

Point of care tests for invasive fungal infections: a blueprint for increasing availability in Africa

Invasive fungal infections (IFIs) such as cryptococcosis, disseminated histoplasmosis, and chronic pulmonary aspergillosis are significant causes of morbidity and mortality in Africa. Lack of laboratory infrastructure and laboratory personnel trained in diagnostic mycology hamper prompt detection and management of IFIs on the continent. Point-of-care tests (POCT) obviate the need for complex infrastructure, skilled technicians, and stable electricity and have had major impacts on the diagnosis of bacterial, viral, and parasitic infections in low- and middle-income countries. Over the last 10 years, POCTs for IFIs have become increasingly available and they have the potential to revolutionize the management of these infections if scaled up in Africa. At the beginning of 2021, the World Health Organization (WHO) Essential Diagnostic List (EDL) included a cryptococcal antigen test for the diagnosis of cryptococcosis, Histoplasma antigen test for the diagnosis of disseminated histoplasmosis, and Aspergillus-specific test for the diagnosis of chronic pulmonary aspergillosis. All of these are available in formats that may be used as POCTs and it is hoped that this will improve the diagnosis of these life-threatening IFIs, especially in low- and middle-income countries. This perspective review discusses commercially available POCTs and outlines strategies of a blueprint to achieve their roll-out in Africa. The strategies include raising awareness, conducting research that uncovers the exact burden of IFIs, increasing advocacy, integrating diagnosis of IFIs into existing public health programs, adoption of the WHO EDL at country levels, and improving logistics and supply chains.

Nucleic acid analysis on paper substrates (NAAPs): an innovative tool for Point of Care (POC) infectious disease diagnosis

The cost-effective rapid diagnosis of infectious diseases is an essential and important factor for curing such diseases in the global public health care picture. Owing to poor infrastructure and lack of sanitation, these diseases have an extreme impact on remote and rural areas, especially in developing countries, and there are unresolved challenges. Molecular diagnosis, such as nucleic acid analysis, plays a key role in the significant treatment of numerous infectious diseases. Current molecular diagnostic assays require a sophisticated laboratory setup with expensive components. Molecular diagnosis on a microfluidic point-of-care (POC) platform is attractive to researchers for disease detection with proper prevention. Compared to various microfluidic substrate materials, paper-based POC technologies offer significant cost-effective solutions over high-cost clinical instruments to fill the gap between the needs of users and affordability. Low-cost paper-based microfluidic POC technologies provide portable and disposable diagnostic systems for multiple disease detection that may be extremely useful in remote areas. This article presents a critical review of paper-based microfluidic device technology which has become an imminent platform to adjust the current health scenario for the detection of diseases using different stages of nucleic acid analysis, such as extraction, amplification and detection of nucleic acid, with future perspectives for paper substrates.

HIV supply chains in low- and middle-income countries: overview and research opportunities

Purpose

Despite HIV being reported as one of the major global health issues, availability and accessibility of HIV services and supplies remain limited, especially in low- and middle-income countries. The effective and efficient operation of HIV supply chains is critical to tackle this problem. The purpose of this paper is to give an introduction to HIV supply chains in low- and middle-income countries and identify research opportunities for the operations research/operations management (OR/OM) community.

Design/methodology/approach

First, the authors review a combination of the scientific and grey literature, including both qualitative and quantitative papers, to give an overview of HIV supply chain operations in low- and middle-income countries and the challenges that are faced by organizing such supply chains. The authors then classify and discuss the relevant OR/OM literature based on seven classification criteria: decision level, methodology, type of HIV service modeled, challenges, performance measures, real-life applicability and countries covered. Because research on HIV supply chains in low- and middle-income countries is limited in the OR/OM field, this part also includes papers focusing on HIV supply chain modeling in high-income countries.

Findings

The authors conclude this study by identifying several tendencies and gaps and by proposing future research directions for OR/OM research.

Originality/value

To the best of the authors’ knowledge, this paper is the first literature review addressing this specific topic from an OR/OM perspective.

An innovative and user-friendly smartphone-assisted molecular diagnostic approach for rapid detection of canine vector-borne diseases

Present-day diagnostic tools and technologies for canine diseases and other vector-borne parasitic diseases hardly meet the requirements of an efficient and rapid diagnostic tool, which can be suitable for use at the point-of-care in resource-limited settings. Loop-mediated isothermal amplification (LAMP) technique has been always a method of choice in the development and validation of quick, precise, and sensitive diagnostic assays for pathogen detection and to reorganize point-of-care (POC) molecular diagnostics. In this study, we have demonstrated an efficient detection system for parasitic vector-borne pathogens like Ehrlichia canis and Hepatozoon canis by linking the LAMP assay to a smartphone via a simple, inexpensive, and a portable “LAMP box,” All the components of the LAMP box were connected to each other wirelessly. This LAMP box was made up of an isothermal heating pad mounted below an aluminum base which served as a platform for the reaction tubes and LAMP assay. The entire setup could be connected to a smartphone via an inbuilt Wi-Fi that allowed the user to establish the connection to control the LAMP box. A 5 V USB power source was used as a power supply. The sensitivity of the LAMP assay was estimated to be up to 10⁻⁶ dilution limit using the amplified, purified, and quantified specific DNA templates. It can also serve as an efficient diagnostic platform for many other veterinary infectious or parasitic diseases of zoonotic origin majorly towards field-based diagnostics.

Protocol for a randomised feasibility study of Point-Of-care HIV viral load testing to Enhance Re-suppression in South Africa: the POwER study

INTRODUCTION

Access to HIV viral load testing remains difficult for many people on antiretroviral therapy (ART) in low-income and middle-income countries. Weak laboratory and clinic systems often delay the detection and management of viraemia, which can lead to morbidity, drug resistance and HIV transmission. Point-of-care testing could overcome these challenges. We aim to assess whether it is feasible to conduct a randomised trial of point-of-care viral load testing to manage viraemia.

METHODS AND ANALYSIS

We will conduct an open-label, single-site, individually randomised, feasibility study of Point-Of-care HIV viral load testing to Enhance Re-suppression, in Durban, South Africa. We will enrol approximately 100 people living with HIV who are aged ≥18 years, receiving first-line ART but with recent viraemia ≥1000 copies/mL, and randomise them 1:1 to receive point-of-care viral load or standard laboratory viral load monitoring, after 12 weeks. All participants will continue to receive care from public sector healthcare workers following South African HIV management guidelines. Participants with persistent viraemia ≥1000 copies/mL will be considered for switching to second-line ART. We will compare the proportion in each study arm who achieve the primary outcome of viral suppression <50 copies/mL at 24 weeks after enrolment. Additional outcomes include proportions retained in the study, proportions with HIV drug resistance, time to viral load results and time to switching to second-line ART. We will assess implementation of point-of-care viral load testing using process evaluation data, and through interviews and focus groups with healthcare workers.

ETHICS AND DISSEMINATION

University of Oxford Tropical Research Ethics Committee and the Biomedical Research Ethics Committee of the University of KwaZulu-Natal have approved the study. We will present results to stakeholders, and through conferences and open-access, peer-reviewed journals.

TRIAL REGISTRATION NUMBER

PACTR202001785886049.

Improving the sensitivity of cellulose fiber-based lateral flow assay by incorporating a water-dissolvable polyvinyl alcohol dam

Lateral flow assay (LFA) is an important point-of-care (POC) test platform due to the associated portability, on-site testing, and low cost for diagnosis of pathogen infections and disease biomarkers. However, compared to high-end analyzers in hospitals, LFA devices, in particular, paper- based LFA tests, fall short in accuracy. This study focuses on two ways to improve LFAs: (1) using cellulose fibers, rather than glass fibers for a sample pad, and (2) incorporating a one-step simple, facile, and low cost PVA dam into the LFA. Both strategies (cellulose fiber as a sample pad and water dissolvable PVA dam) contributed to delaying the controlled biomolecule's flow through the nitrocellulose membrane's capillary channels resulting in increased bio-recognition time, thus contributing to the enhancement of LFA sensitivity. PVA modified cellulose fiber-based LFA demonstrated 10 times higher sensitivity than the cellulose fiber-based unmodified LFA, whereas 2 times enhancement was obtained in the cellulose fiber-based sample pad LFA compared to the glass fiber-based sample pad LFA. Ultimately, 20 times increase in sensitivity was achieved in the modified LFA device. This study shows that PVA and eco-friendly cellulose fibers could be incorporated into other paper based POC testing devices for future development.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10570-021-04083-3.

Quantum Dots: An Emerging Tool for Point-of-Care Testing

Quantum dots (QDs) are semiconductor crystals in the nanodimension having unique optical and electronic properties that differ from bulk material due to quantum mechanics. The QDs have a narrow emission peak, size-dependent emission wavelength, and broad excitation range which can be utilized for diverse biomedical applications such as molecular imaging, biosensing, and diagnostic systems. This article reviews the current developments of biomedical applications of QDs with special reference to point-of-care testing.

Engineering Protein Switches for Rapid Diagnostic Tests

Biological signaling pathways are underpinned by protein switches that sense and respond to molecular inputs. Inspired by nature, engineered protein switches have been designed to directly transduce analyte binding into a quantitative signal in a simple, wash-free, homogeneous assay format. As such, they offer great potential to underpin point-of-need diagnostics that are needed across broad sectors to improve access, costs, and speed compared to laboratory assays. Despite this, protein switch assays are not yet in routine diagnostic use, and a number of barriers to uptake must be overcome to realize this potential. Here, we review the opportunities and challenges in engineering protein switches for rapid diagnostic tests. We evaluate how their design, comprising a recognition element, reporter, and switching mechanism, relates to performance and identify areas for improvement to guide further optimization. Recent modular switches that enable new analytes to be targeted without redesign are crucial to ensure robust and efficient development processes. The importance of translational steps toward practical implementation, including integration into a user-friendly device and thorough assay validation, is also discussed.

Paper/Soluble Polymer Hybrid-Based Lateral Flow Biosensing Platform for High-Performance Point-of-Care Testing

As a global shift continues to occur in high burden diseases toward developing countries, the importance of medical diagnostics based on point-of-care testing (POCT) is rapidly increasing. However, most diagnostic tests that meet clinical standards rely on high-end analyzers in central hospitals. Here, we report the development of a simple, low-cost, mass-producible, highly sensitive/quantitative, automated, and robust paper/soluble polymer hybrid-based lateral flow biosensing platform, paired with a smartphone-based reader, for high-performance POCT. The testing architecture incorporates a polymeric barrier that programs/automates sequential reactions via a polymer dissolving mechanism. The smartphone-based reader with simple opto-mechanical parts offers a stable framework for accurate quantification. Analytical performance of this platform was evaluated by testing human cardiac troponin I (cTnI), a preferred biomarker for the diagnosis of myocardial infarction, in serum/plasma samples. Coupled with catalytic/colorimetric gold-ion amplification, this platform produced results within 20 min with a detection limit of 0.92 pg mL^-1 and a coefficient of variation <10%, which is equivalent to the performance of a high-sensitivity standard analyzer, and operated within acceptable levels stipulated by clinical guidelines. Moreover, cTnI clinical sample tests indicate a high correlation (r = 0.981) with the contemporary analyzers, demonstrating the clinical utility of this platform in high-performance POCT.

Continuous quality monitoring in the field: an evaluation of the performance of the Fio Deki Reader™ for rapid HIV testing in South Africa

Background

Rapid diagnostic tests (RDTs) are a cornerstone of HIV diagnosis and rely on good quality processing and interpretation, particularly in the era of test and treat. The Deki Reader (Fio Corporation®, Toronto, Ontario, Canada) is a portable device designed specifically for analysing RDTs and was selected for evaluation in South Africa in the context of HIV RDT analysis.

Methods

This study consisted of a laboratory evaluation and two-part field evaluation of the Deki Reader v100, covering two RDT testing algorithms, and an evaluation of the continuous quality monitoring through the Fionet™ web portal. Based on user feedback from the field evaluation, the device underwent hardware and software redesign, and the Deki Reader v200 was evaluated in the laboratory. Ethics approval for this evaluation was obtained from the University of the Witwatersrand Human Research Ethics Committee: M150160.

Results

The intra- and inter-device laboratory precision of the Deki Reader v100 were 98.3 and 99.2% respectively, and 99.3 and 100% for the Deki Reader v200. The laboratory concordances compared to standard-of-care reporting were 99.5 and 98.0% for the two respective models, while sensitivity and specificity were 99.5 and 99.4% for the Deki Reader V100 and 100 and 93.1% for the Deki Reader V200 respectively. Screening and confirmatory concordances in the field were 99.3 and 96.5% under algorithm 1 and 99.7 and 100% under algorithm 2. Sensitivity and specificity for the field evaluation were 99.8 and 97.7%. Overall robustness of the device was acceptable and continuous quality monitoring through Fionet™ was feasible.

Conclusions

The Deki Reader provides an option for improved and reliable quality assessment for rapid diagnosis of HIV using RDTs to enhance the quality of healthcare at the point-of-care. However, the introduction of new RDTs and modification of current algorithms necessitates ongoing and agile RDT reader adjustments, which will require cost modelling to ensure sustainability of devices implemented into national HIV programs.

Assessment of the Impact of Rapid Point-of-Care CD4 Testing in Primary Healthcare Clinic Settings: A Survey Study of Client and Provider Perspectives

BACKGROUND

The high burden of disease in South Africa presents challenges to public health services. Point-of-care (POC) technologies have the potential to address these gaps and improve healthcare systems. This study ascertained the acceptability and impact of POC CD4 testing on patients' health and clinical management.

METHODS

We conducted a qualitative survey study with patients (n = 642) and healthcare providers (n = 13) at the Lancers Road (experienced POC) and Chesterville (non-experienced POC) primary healthcare (PHC) clinics from September 2015 to June 2016.

RESULTS

Patients (99%) at Lancers and Chesterville PHCs were positive about POC CD4 testing, identifying benefits: No loss/delay of test results (6.4%), cost/time saving (19.5%), and no anxiety (5.1%), and 58.2% were ready to initiate treatment. Significantly more patients at Chesterville than Lancers Road PHC felt POC would provide rapid clinical decision making (64.7% vs. 48.1%; p < 0.0001) and better clinic accessibility (40.4% vs. 24.7%; p < 0.0001) respectively. Healthcare providers thought same-day CD4 results would impact: Clinical management (46.2%), patient readiness (46.2%), and adherence (23.0%), and would reduce follow-up visits (7.7%), while 38.5% were concerned that further tests and training (15.4%) were required before antiretroviral therapy (ART) initiation.

CONCLUSION

The high acceptability of POC CD4 testing and the immediate health, structural, and clinical management benefits necessitates POC implementation studies.

Affimer-Enzyme-Inhibitor Switch Sensor for Rapid Wash-free Assays of Multimeric Proteins

Robust technology is required to underpin rapid point-of-care and in-field diagnostics to improve timely decision making across broad sectors. An attractive strategy combines target recognition and signal generating elements into an "active" enzyme-switch that directly transduces target-binding into a signal. However, approaches that are broadly applicable to diverse targets remain elusive. Here, an enzyme-inhibitor switch sensor was developed by insertion of non-immunoglobulin Affimer binding proteins, between TEM1-β-lactamase and its inhibitor protein, such that target binding disrupts the enzyme-inhibitor complex. Design principles for a successful switch architecture are illustrated by the rapid (min), simple (wash-free), and sensitive (pM) quantification of multimeric target analytes in biological samples (serum, plasma, leaf extracts), across three application areas. A therapeutic antibody (Herceptin), protein biomarker (human C-reactive protein), and plant virus (cow pea mosaic virus) were targeted, demonstrating assays for therapeutic drug monitoring, health diagnostics, and plant pathogen detection, respectively. Batch-to-batch reproducibility, shelf-life stability, and consistency with validated enzyme-linked immunosorbent assay analysis confirm that the principle of an Affimer-enzyme-inhibitor switch provides a platform for point-of-care and in-field diagnostics.

Performance of Cepheid Xpert HIV-1 viral load plasma assay to accurately detect treatment failure

BACKGROUND

Coverage of viral load testing remains low with only half of the patients in need having adequate access. Alternative technologies to high throughput centralized machines can be used to support viral load scale-up; however, clinical performance data are lacking. We conducted a meta-analysis comparing the Cepheid Xpert HIV-1 viral load plasma assay to traditional laboratory-based technologies.

METHODS

Cepheid Xpert HIV-1 and comparator laboratory technology plasma viral load results were provided from 13 of the 19 eligible studies, which accounted for a total of 3790 paired data points. We used random effects models to determine the accuracy and misclassification at various treatment failure thresholds (detectable, 200, 400, 500, 600, 800 and 1000 copies/ml).

RESULTS

Thirty percent of viral load test results were undetectable, while 45% were between detectable and 10 000 copies/ml and the remaining 25% were above 10 000 copies/ml. The median Xpert viral load was 119 copies/ml and the median comparator viral load was 157 copies/ml, while the log10 bias was 0.04 (0.02-0.07). The sensitivity and specificity to detect treatment failure were above 95% at all treatment failure thresholds, except for detectable, at which the sensitivity was 93.33% (95% confidence interval: 88.2-96.3) and specificity was 80.56% (95% CI: 64.6-90.4).

CONCLUSION

The Cepheid Xpert HIV-1 viral load plasma assay results were highly comparable to laboratory-based technologies with limited bias and high sensitivity and specificity to detect treatment failure. Alternative specimen types and technologies that enable decentralized testing services can be considered to expand access to viral load.

Cotton fiber-based assay with time-based microfluidic absorption sampling for point-of-care applications

Aim: Time-based microfluidic absorption sampling was proposed using cotton fiber-based device made in swab stick. The assay was optimized and compared with conventional pipetted drop sampling using the same device. Materials & methods: Reagents were integrated into cotton fiber device for assessing concentration of analytes by the colorimetric detection method through time-based absorption sampling microfluidic system. All assay parameters were first optimized using conventional pipette-based drop sampling. Results: The color intensity is linear in the relevant concentration range of the analytes. The LOD are 0.189 mM for glucose and 6.56 μM for nitrite, respectively. These values are better than conventional drop sampling. The fiber-containing swab itself functions as sampling, assay and calibration device. Conclusion: Microfluidic cotton fiber-based assay device was fabricated and can determine analyte concentration in artificial salivary samples, colorimetrically, by time-based absorption sampling without the need of complex equipments.

Performance of non-laboratory staff for diagnostic testing and specimen collection in HIV programs: A systematic review and meta-analysis

BACKGROUND

In most high HIV burden countries, many HIV patients do not have reliable access to required diagnostic laboratory tests. Task shifting of clinical tasks to lower cadres of health care workers and lay counselors has been successful in scaling up treatment for HIV and may also be an effective strategy in expanding access to essential diagnostic testing.

METHODS

We screened major electronic databases between 1 January 2005 to 26 August 2018 to identify studies assessing ease of use and accuracy of task shifting of HIV-related diagnostic testing and/or specimen collection to non-laboratory health staff. Two independent reviewers screened all titles and abstracts for studies that analyzed diagnostic accuracy, patient impact, ease-of-use, or cost-effectiveness. Studies were assessed for quality, bias, and applicability following the QUADAS-2 framework. We generated summary estimates using random-effects meta-analyses.

RESULTS

We identified 42 relevant studies. Overall, point-of-care CD4 testing performed by non-laboratory staff had a mean bias of -54.44 (95% CI: -72.40 --36.48) compared to conventional laboratory-based. Though studies were limited, the diagnostic accuracy of point-of-care alanine transaminase enzyme (ALT) and hemoglobin testing performed by non-laboratory staff was comparable to conventional laboratory-based testing by laboratory professionals. Point-of-care testing and/or specimen collection were generally found to be acceptable and easy to use for non-laboratory staff.

CONCLUSIONS

Task shifting of testing using point-of-care technologies to non-laboratory staff was comparable to laboratory professionals operating the same technology in the laboratory. Some variability was observed comparing the performance of point-of-care CD4 testing by non-laboratory staff to conventional laboratory-based technologies by laboratory professionals indicating potential lower performance was likely technological rather than operator caused. The benefits of task shifting of testing may outweigh any possible harms as task shifting allows for increased decentralization, access of specific diagnostics, and faster result delivery.

Driving the route of laboratory medicine: a manifesto for the future

The role of laboratory medicine is essential in healthcare, since in vitro diagnostic testing represents now an unavoidable part of reasoning and clinical decision making. Laboratory tests are an essential part of most care pathways, aimed at optimizing resource utilization and improving patient outcome. The activity of laboratory professionals is interconnected with all medical disciplines, and provides a crucial support for ordering the right test, for the right patient and at the right time, but also helps interpreting and using laboratory data. Although recent advancement in laboratory medicine, catalyzed by technical innovations and development of innovative tests, have promoted a substantial revolution in the organization of clinical laboratories, the future of this profession seems still ambiguous. We have hence developed a "manifesto" of laboratory medicine, meant to promote an innovative prospect of our discipline and encouraging the establishment of a new generation of laboratory professionals and managers.

Toward Improving Accessibility of Point-of-Care Diagnostic Services for Maternal and Child Health in Low- and Middle-Income Countries

Point-of-care (POC) testing can improve health care provision in settings with limited access to health care services. Access to POC diagnostic services has shown potential to alleviate some diagnostic challenges and delays associated with laboratory-based methods in low- and middle-income countries. Improving accessibility to POC testing (POCT) services during antenatal and perinatal care is among the global health priorities to improve maternal and child health. This review provides insights on the availability of POC testing designed for diagnosing HIV, syphilis, and malaria in pregnancy to improve maternal and child health. In addition, factors such as accessibility of POC testing, training of health work force, and the efficiency of POC testing services delivery in low- and middle-income countries are discussed. A framework to help increase access to POC diagnostic services and improve maternal and child health outcomes in low- and middle-income countries is proposed.

Implementation science: point-of-care diagnostics in HIV and tuberculosis

Implementation science uses methods to promote the scaling up and use of evidence-based practices by health systems to improve quality and outcomes. Its use is vital to maximise the efficiency of limited resources for health care in tropical settings. HIV and tuberculosis (TB) are two of the major causes of morbidity and mortality in sub-Saharan Africa, and globally. Although effective treatments are widely available, lack of diagnosis remains a large barrier to accessing treatment, particularly in resource-limited settings. We explore HIV and TB diagnostics that can be used at point-of-care in any settings, and outline some important principles and applications of implementation science to aid their application and use. Despite robust evidence of diagnostic accuracy and efficacy in improving patient-centred outcomes, such interventions cannot be fully utilised without addressing operational barriers and knowledge gaps.

Poor supply chain management and stock-outs of point-of-care diagnostic tests in Upper East Region's primary healthcare clinics, Ghana

INTRODUCTION

Several supply chain components are important to sustain point-of-care (POC) testing services in rural settings. To evaluate the availability of POC diagnostic tests in rural Ghana's primary healthcare (PHC) clinics, we conducted an audit of the supply chain management for POC diagnostic services in rural Upper East Region's (UER) PHC clinics, Ghana to determine the reasons/causes of POC tests deficiencies.

MATERIAL AND METHODS

We conducted a review of accessible POC diagnostics in 100 PHC clinics in UER, Ghana from February to March 2018. We used a monitoring audit tool adopted from the World Health Organization and Management Science for Health guidelines for supply chain management of diagnostics for compliance. We determined a clinic's compliance with the stipulated guidelines, and a composite compliant score was defined as a percentage rating of 90 to 100%. We used univariate logistic regression analysis in Stata 14 to determine the level of association between supply chain management and the audit variables.

RESULTS

Overall, the composite compliant score of supply chain management for existing POC tests was at 81% (95%CI: 79%-82%). The mean compliance with distribution guidelines was at 93.8% (95%CI: 91.9%-95.6%) the highest score, whilst inventory management scored the lowest, at 53.5% (95%CI: 49.5%-57.5%) compliance. Of the 13 districts in the region, the results showed complete stock-out of blood glucose test in all selected PHC clinics in seven (53.8%) districts, haemoglobin and hepatitis B virus test in three (23.1%), and urine protein test in two (15.4%) districts. Based on our univariate logistics regression models, stock-out of tests at the Regional Medical and District Health Directorates stores in the region, high clinic attendance, lack of documentation of expiry date/expired tests, poor documentation of inventory level, poor monitoring of monthly consumption level, and failure to document unexplained losses of the various POC tests were significant predictors of complete test stock-out in most of the clinics in the Upper East Region.

DISCUSSION

There is poor supply chain management of POC diagnostic tests in UER's PHC clinics. Improvement in inventory management and human resource capacity for POC testing is critical to ensure accessibility and sustainability of POC diagnostic services in resource-limited settings PHC clinics.

Profile of the SeptiCyte™ LAB gene expression assay to diagnose infection in critically ill patients

Sepsis is a severe and frequently occurring clinical syndrome, caused by the inflammatory response to infections. Recent studies on the human transcriptome during sepsis have yielded several gene-expression assays that might assist physicians during clinical assessment of patients suspected of sepsis. SeptiCyte™ LAB (Immunexpress, Seattle, WA) is the first gene expression assay that was cleared by the FDA in the United States to distinguish infectious from non-infectious causes of systemic inflammation in critically ill patients. The test consists of the simultaneous amplification of four RNA transcripts (CEACAM4, LAMP1, PLAC8, and PLA2G7) in whole blood using a quantitative real-time PCR reaction. This review provides an overview of the challenges in the diagnosis of sepsis, the development of gene expression signatures, and a detailed description of available clinical performance studies evaluating SeptiCyte™ LAB.

Teaching the pony new tricks: competences for specialists in laboratory medicine to meet the challenges of disruptive innovation

The 20th century digital revolution has already seen the introduction of faster, more diverse, easier to use technologies with extended capacity and capability that has enhanced productivity in Laboratory Medicine and allowed more effective use of human resource. With increasing demands for better health and best care the challenge to future healthcare systems is to deploy technology, facilities and human resources more effectively. For the 21st century the digital age heralds opportunities for information-led technology providers to become healthcare providers when algorithm driven care can support patients’ needs at the point of care close to or in their homes. For Specialists in Laboratory Medicine the opportunity arises for working beyond the laboratory in partnership with the emerging providers. The challenge to specialists is to extend their skill and competence to leadership roles that (a) determine clinical need and strategic direction for local environments, (b) ensure technology solutions are cost-effective, safe and reliable, (c) assume the business acumen to market, negotiate and manage change in services, (d) expect understanding of the clinical bioinformatics that underpin genomics, health information science (data mining and health economics) and physical sciences (e) expect knowledge and skills in the provision of direct clinical care in the face of staffing shortfalls experienced by many healthcare systems and (f) enhance their communication and interactive skills. In growing their leadership contribution a partnership approach in education and training across healthcare divides, in conjunction with the diagnostics and/or information technology industries, through integrated professional organisation approaches, joint approaches with academia and policy related healthcare organisations is recommended.

New virological tools for screening, diagnosis and monitoring of hepatitis B and C in resource-limited settings

Worldwide, the increasingly dominant model of laboratory testing is the centralised laboratory, in which automation of analytical processes increases, enabling the analysis of large numbers of samples at a relatively low cost. However, this trend does not fulfil the requirements for care of patients with chronic hepatitis B and C in resource-limited settings. Alternative models using point-of-care (POC) tests and dried blood spots (DBSs) are increasingly being considered for viral hepatitis screening, diagnosis and monitoring. POC tests are small devices providing qualitative and/or quantitative determination of viral antibodies and/or antigens. They can use original specimen matrices, such as oral fluid or blood collected from a fingerstick. POC tests are particularly useful for large-scale screening, and to improve access to care in regions where laboratory access is limited. New POC devices that detect and quantify viral nucleic acids are at the developmental stage. DBSs offer the main advantage of enabling storage of desiccated blood that can be easily transported to reference centres, where state-of-the-art molecular and serological diagnostic tests are available. However, standardisation and better automation of DBS handling are needed. Herein, we review alternatives to classical hepatitis B and C virological tests, examining POC tests and DBSs, as well as alternatives to nucleic acid testing. Innovations in testing approaches resulting from the availability of these new assays are also discussed.

A portable device for nucleic acid quantification powered by sunlight, a flame or electricity

A decentralized approach to diagnostics can decrease the time to treatment of infectious diseases in resource-limited settings. Yet most modern diagnostic tools require stable electricity and are not portable. Here, we describe a portable device for isothermal nucleic-acid quantification that can operate with power from electricity, sunlight or a flame, and that can store heat from intermittent energy sources, for operation when electrical power is not available or reliable. We deployed the device in two Ugandan health clinics, where it successfully operated through multiple power outages, with equivalent performance when powered via sunlight or electricity. A direct comparison between the portable device and commercial qPCR (quantitative polymerase chain reaction) machines for samples from 71 Ugandan patients (29 of which were tested in Uganda) for the presence of Kaposi’s sarcoma-associated herpesvirus DNA showed 94% agreement, with the four discordant samples having the lowest concentration of the herpesvirus DNA. The device’s flexibility in power supply provides a needed solution for on-field diagnostics.

Establishing an ambulatory care service using point-of-care testing diagnostics

The use of ambulatory emergency care services in the NHS has been shown to reduce the emergency inpatient burden and enhance the overall patient experience, while demonstrating a cost saving to the NHS. At the James Paget University Hospital point-of-care testing was used as an enabler within an evidence-based lean service redesign to successfully set up a novel unit. A 3-month pilot period, with limited operational times, showed a dramatic improvement in patient flow through the acute medicine pathway, with an equivalent of 59 bed days saved during the pilot period. Further expansion of the unit to a dedicated area with full 7-day opening allowed a continued improvement in performance. This resulted in a mean length of stay of 115 minutes (a 54% reduction from pre-baseline), and just 6.1% of an average of 18.1 daily attendances were converted to full admission. This demonstrated a clinical, operational and financial benefit, allowing improved clinical outcomes.

A Simple Imaging Device for Fluorescence-Relevant Applications

This article unveiled the development of an inexpensive, lightweight, easy-to-use, and portable fluorescence imaging device for paper-based analytical applications. We used commercial fluorescent dyes, as proof of concept, to verify the feasibility of our fluorescence imaging device for bioanalysis. This approach may provide an alternative method for nucleotide detection and semen analysis, using a miniaturized fluorescence reader that is more compact and portable than conventional analytical equipment.

Detection of 1,5-anhydroglucitol as a Biomarker for Diabetes Using an Organic Field-Effect Transistor-Based Biosensor

Sensor devices that can be fabricated on a flexible plastic film produced at a low cost using inkjet-printing technology are suitable for point-of-care applications. An organic field-effect transistor (OFET)-based biosensor can function as a potentiometric electrochemical sensor. To investigate the usefulness of an OFET-based biosensor, we demonstrated the detection of 1,5-anhydroglucitol (1,5-AG) and glucose, which are monosaccharides used as biomarkers of diabetes. An OFET-based biosensor combined with a Prussian blue (PB) electrode, modified with glucose oxidase (GOx) or pyranose oxidase (POx), was utilized for the detection of the monosaccharides. When the GOx- or POx-PB electrode was immersed in glucose solution at the determined concentration, shifts in the low-voltage direction of transfer characteristic curves of the OFET were observed to be dependent on the glucose concentrations in the range of 0–10 mM. For 1,5-AG, the curve shifts were observed only with the POx-PB electrode. Detection of glucose and 1,5-AG was achieved in a substrate-specific manner of the enzymes on the printed OFET-biosensor. Although further improvements are required in the detection concentration range, the plastic-filmOFET-biosensors will enable the measurement of not only diabetes biomarkers but also various other biomarkers.

Shifting the HIV Paradigm from Care to Cure: Proceedings from the Caribbean Expert Summit in Barbados, August 2017

The CCAS EXPERT SUMMIT convened an array of international experts in Barbados on August 27-31, 2017 under the theme "From Care to Cure-Shifting the HIV Paradigm." The Caribbean Cytometry & Analytical Society (CCAS) partnered with the Joint United Nations Programme on HIV/AIDS (UNAIDS) to deliver a program that reviewed the advances in antiretroviral therapy and the public health benefits accruing from treatment as prevention. Particular emphasis was placed on reexamining stigma and discrimination through a critical appraisal of whether public health messaging and advocacy had kept pace with the advances in medicine. Persistent fear of HIV driving discriminatory behavior was widely reported in different regions and sectors, including the healthcare profession itself; continued fear of the disease was starkly misaligned with the successes of new medical treatments and progress toward the UNAIDS 90-90-90 targets. The summit therefore adopted the mantra "Test-Treat-Defeat" to help engage with the public in a spirit of optimism aimed at creating a more conducive environment for persons to be tested and treated and, thereby, help reduce HIV disease and stigma at the individual and community levels.

Performance of point-of-care birth HIV testing in primary health care clinics: An observational cohort study

BACKGROUND

Failure to timely diagnose HIV in infants is a major barrier for scaling-up paediatric antiretroviral treatment (ART). WHO recommends birth testing for earlier diagnosis and to improve test coverage, but current diagnosis takes 2-3 weeks to complete, thereby limiting the ability of care givers to provide follow-on care, especially in low-resource settings. We evaluated the benefit of implementing rapid diagnosis of HIV at birth in primary health care maternity wards in Mozambique.

METHODS AND FINDINGS

Infants born to HIV-infected mothers delivering consecutively at eight primary health care clinics were tested within 24 hours of delivery using on-site POC (Alere q HIV1/2 Detect) and standard laboratory (Roche COBAS AmpliPrep/TaqMan HIV-1 qualitative assay v2.0) testing. Infants were also tested at 4-6 weeks of age with both assays. Of 2,350 HIV-exposed infants enrolled in this implementation research study, 33 tested HIV-positive at birth on both assays. Sensitivity and specificity of POC testing compared with laboratory testing at birth were 100% (95% CI 89·4-100·0) and 100% (95% CI 99·8-100·0), respectively. At 4-6 weeks of age, 61 infants were identified as HIV-positive; of these 29 (47·5%) had a positive test at birth. Testing at both birth and 4-6 weeks identified 71 HIV-positive infants compared with 61 infants by testing at 4-6 weeks alone, a 16% increase. Two infants tested positive at birth but tested HIV-negative during follow-up.

CONCLUSIONS

Adding POC birth testing to the 4-6 week screen may increase access to HIV diagnosis and expedite ART initiation in primary health care settings within low resource settings. Guidance on appropriate confirmatory HIV testing algorithms for birth testing is needed.

Application of a Nanotechnology-Based, Point-of-Care Diagnostic Device in Diabetic Kidney Disease

Introduction

Early detection of diabetes mellitus (DM) and diabetic kidney disease (DKD) is important for preventing end-stage renal failure and reducing cardiovascular complications. Availability of a validated point-of-care (PoC) device that can measure various DKD markers would be useful in this respect, especially in resource-poor parts of the world.

Methods

We validated a novel nanotechnology-based multianalyte PoC device (minimally invasive and does not require trained medical personnel) against laboratory gold standard tests for the detection of 5 biomarkers related to management of DM and DKD. The prospective study was funded by an International Society of Nephrology American Nephrologists of Indian Origin grant in 2 phases: (i) proof of concept: random samples were tested for the analytes with the PoC device and correlated with the laboratory gold standard; and (ii) clinical validation in a well-characterized cohort of patients. A nonenzymatic- and nonantibody-based electrochemical PoC device for quantitative measurement of markers—glycosylated hemoglobin (HbA_1c), hemoglobin, serum albumin, microalbuminuria, urine creatinine, and albumin-to-creatinine ratio−was developed and used in this study. The disposable strips were interfaced with a multipotentiostat hand-held PoC device (3.7-V rechargeable lithium battery, 5-inch touch screen, Bluetooth enabled) working in amperometry mode, which provided the results in <1 minute. Data were analyzed using linearity plots and Bland-Altman difference plot analysis.

Results

A total of 4717 individuals were screened during the study (phase 1: 2576 and phase 2: 2141.) In phase 2, samples were tested in 529 subjects (346 females)—120 subjects with type 1 DM, 255 subjects with type 2 DM, 54 subjects without DM, 400 subjects with stage 2 chronic kidney disease, and 30 subjects with stage 3 chronic kidney disease.

Conclusion

A nanotechnology-based PoC device for quantitative measurement of HbA_1c, hemoglobin, serum albumin, microalbuminuria, and the urine albumin-to-creatinine ratio was developed for detection of early DKD and showed excellent correlation between the device and laboratory results. This device has the potential for early detection of DM and/or DKD, especially in remote communities in underserved areas of the world where prevalence of diabetes is rapidly increasing.

Clinic flow for STI, HIV, and TB patients in an urban infectious disease clinic offering point-of-care testing services in Durban, South Africa

Background

Many clinics in Southern Africa have long waiting times. The implementation of point-of-care (POC) tests to accelerate diagnosis and improve clinical management in resource-limited settings may improve or worsen clinic flow and waiting times. The objective of this study was to describe clinic flow with special emphasis on the impact of POC testing at a large urban public healthcare clinic in Durban, South Africa.

Methods

We used time and motion methods to directly observe patients and practitioners. We created patient flow maps and recorded individual patient waiting and consultation times for patients seeking STI, TB, or HIV care. We conducted semi-structured interviews with 20 clinic staff to ascertain staff opinions on clinic flow and POC test implementation.

Results

Among 121 observed patients, the total number of queues ranged from 4 to 7 and total visit times ranged from 0:14 (hours:minutes) to 7:38. Patients waited a mean of 2:05 for standard-of-care STI management, and approximately 4:56 for STI POC diagnostic testing. Stable HIV patients who collected antiretroviral therapy refills waited a mean of 2:42 in the standard queue and 2:26 in the fast-track queue. A rapid TB test on a small sample of patients with the Xpert MTB/RIF assay and treatment initiation took a mean of 6:56, and 40% of patients presenting with TB-related symptoms were asked to return for an additional clinic visit to obtain test results. For all groups, the mean clinical assessment time with a nurse or physician was 7 to 9 min, which accounted for 2 to 6% of total visit time. Staff identified poor clinic flow and personnel shortages as areas of concern that may pose challenges to expanding POC tests in the current clinic environment.

Conclusions

This busy urban clinic had multiple patient queues, long clinical visits, and short clinical encounters. Although POC testing ensured patients received a diagnosis sooner, it more than doubled the time STI patients spent at the clinic and did not result in same-day diagnosis for all patients screened for TB. Further research on implementing POC testing efficiently into care pathways is required to make these promising assays a success.