Point of Care Testing

Background The National Institute for Health and Care Excellence (NICE) have called for research into the role of biomarkers, and specifically procalcitonin (PCT), for the early diagnosis of serious bacterial infections (SBI) in children. The aim of this study was to compare the diagnostic test accuracy of C-reactive protein (CRP) and PCT for the diagnosis of SBI in children. Methods Data was collected prospectively from four UK emergency departments (ED) between November 2017 and June 2019. Consecutive children under 18 years of age with fever and features of possible sepsis and/or meningitis were eligible for inclusion. The index tests were PCT and CRP and the reference standard was the confirmation of SBI. Results 213 children were included in the final analysis. 116 participants (54.5%) were male, and the median age was 2 years, 9 months. Parenteral antibiotics were given to 100 (46.9%), three (1.4%) were admitted to a paediatric intensive care unit and there were no deaths. The...

Iron deficiency (ID) is an urgent public health problem that has devastating effects on maternal and child health. However, due to poor access and affordability, screening and diagnosis for ID is often limited to proxy hemoglobin measurements alone. Here, we report the development and validation of ironPhone, a mobile-device coupled portable diagnostics for quantification of serum ferritin concentrations, an iron status biomarker, within a few minutes, from a drop of fingerprick blood. The ironPhone diagnostic platform comprises of a smartphone accessory, an app, and a disposable lateral flow immunoassay test strip to quantify serum ferritin. For initial validation in the lab, we optimized and evaluated the performance of ironPhone with known ferritin concentrations in spiked buffer and serum samples. Following lab validation, we performed a human validation by collecting fingerprick whole blood samples from 20 participants to assess iron status using ironPhone and compared the results with the laboratory standard IMMULITE 2000 analyzer. Findings from the ironPhone for the buffer and spiked serum samples provided a calibration curve with R 2 values of 0.97 (n=27) and 0.93 (n=12), respectively. On comparison with the laboratory standard IMMULITE analyzer in whole blood samples, a correlation of 0.92 (P < 0.0001) was observed with a sensitivity of over 90% for predicting ID (ferritin < 15.0 µg/L) via the ironPhone, demonstrating its promise for iron status assessment at the point-of-care.

Objective: This study was done to assess the accuracy of Accutrend GCT meter in determining blood cholesterol levels in our setup, with an aim to recommend its use in clinical practice
Methods: This cross sectional study was conducted on 251 healthy volunteers from April to May 2013. Capillary whole blood samples were obtained using sterile lancets and cholesterol levels were measured using Accutrend GCT meter (Roche Diagnostics, Mannheim, Germany) using the standard technique. Three ml whole blood was also collected in plain tubes by the same operator without applying a tourniquet. Serum cholesterol levels were determined using Merck Microlab 300 Automated Clinical Chemistry Analyser the same day. The laboratory technician performing this test was blinded to results obtained with Accutrend GCT meter. The seven patients with readings beyond the analytic range of the Accutrend GCT meter were excluded, meaning that data analysis was performed on 244 results only.
Results: Results of 182 males and 62 females having a mean age of 38.54± 15.25 years were analysed. There was a significant difference in mean cholesterol levels measured by Accutrend GCT and Microlab-300 (4.73± 0.74mmol/l and 4.67± 0.86 mmol/l; p=0.021), producing a measurement bias of 1.43% with Accutrend GCT meter. A strong positive correlation was found between the results of the two techniques (r=0.852 ,p<0.001).
Conclusions: Accutrend GCT meter provides accurate measurement of blood cholesterol levels and its use should be encouraged for point-of-care measurements.

A Point of Care (POC) test for measurement of antibody or cortisol concentrations has given rapid feedback to coaches and support staff in Premier League soccer clubs within a matter of minutes from sample collection.  This has been useful in assessing fatigue levels, immune status and readiness to train / compete and offers a considerable time advantage over standard laboratory methods.  This current paper assesses a new POC reader, which is smaller, quicker and cheaper than the current model.
A total of 48 saliva samples taken during routine monitoring a cohort of English Premier League soccer players (23.5 ± 6.4 yrs) using IPRO OFC kits on two separate occasions for the measurement of cortisol on the standard IPRO ESE-Quant LFD reader and the new IPRO Cube reader.  The next week 50 samples from the same cohort were measured for sIgA concentration with the IPRO Cube reader and the same samples analysed the next day via ELISA.
The cortisol LFD showed good agreement on both readers; r = 0.96 (95% CI 0.93 – 0.98) with typical error of estimate 1.18 nM (95% CI 0.98 – 1.48) and no difference between the mean values on each reader: ESE-Quant 7.5 nM (range 2.73 – 23.5 nM) v Cube 7.1 nM (range 2.24 – 25.8).
The sIgA LFD measured with the Cube reader showed good agreement with ELISA r = 0.97 (95% CI 0.95 – 0.98) with typical error of estimate 33.24 μg/mL and no difference between the mean values on the Cube and ELISA: Cube mean 215.6 ± 163.8 μg/mL (range 34.7 – 621.1 μg/mL) v ELISA mean 205.4 ± 142.1 (range 34.91 600 μg/mL.
The new Cube POC device shows suitable validity for use in the sporting environment and represents savings in cost and analysis time in comparison to previous methods.

The deleterious effects of the coronavirus disease 2019 (COVID-19) pandemic urged the development of diagnostic tools to manage the spread of disease. Currently, the &quot;gold standard&quot; involves the use of quantitative real-time polymerase chain reaction (qRT-PCR) for SARS-CoV-2 detection. Even though it is sensitive, specific and applicable for large batches of samples, qRT-PCR is labour-intensive, time-consuming, requires trained personnel and is not available in remote settings. This review summarizes and compares the available strategies for COVID-19: serological testing, Point-of-Care Testing, nanotechnology-based approaches and biosensors. Last but not least, we address the advantages and limitations of these methods as well as perspectives in COVID-19 diagnostics. The effort is constantly focused on understanding the quickly changing landscape of available diagnostic testing of COVID-19 at the clinical levels and introducing reliable and rapid screening point of care te...

All clinical laboratory testing in the United States is regulated by the Clinical Laboratory Improvement Amendments of 1988 (CLIA&#39;88 or CLIA) and overseen by the Centers for Medicare and Medicaid Services. CLIA profoundly changed the prevailing United States regulatory philosophy by imposing uniform requirements for all clinical laboratory testing regardless of where tests are performed. In the hospital, regulatory compliance is usually ensured by regular inspections of the laboratory by either the Joint Commission or by the College of American Pathologists. These organizations may include requirements beyond the minimum standard mandated by CLIA. This article reviews the status of regulatory compliance of point-of-care testing from a perspective of the current regulations in effect in the United States in 2009.

Point-of-care testing (POCT) refers to any diagnostic test administered outside the central laboratory at or near the location of the patient. By performing the sample collection and data analysis steps in the same location POCT cuts down on transport and processing delays, resulting in the rapid feedback of test results to medical decision-makers. Over the past decades the availability and use of POCT have steadily increased in Europe and throughout the international community. However, concerns about overall utility and the reliability of benefits to patient care have impeded the growth of POCT in some areas. While there is no agreed-upon standard for how success should be judged, the increases in speed and mobility provided by POCT can lead to substantial advantages over traditional laboratory testing. When properly utilized, POCT has been shown to yield measurable improvements in patient care, workflow efficiency, and even provide significant financial benefits. However, importa...

The deleterious effects of the coronavirus disease 2019 (COVID-19) pandemic urged the development of diagnostic tools to manage the spread of disease. Currently, the “gold standard” involves the use of quantitative real-time polymerase chain reaction (qRT-PCR) for SARS-CoV-2 detection. Even though it is sensitive, specific and applicable for large batches of samples, qRT-PCR is labour-intensive, time-consuming, requires trained personnel and is not available in remote settings. This review summarizes and compares the available strategies for COVID-19: serological testing, Point-of-Care Testing, nanotechnology-based approaches and biosensors. Last but not least, we address the advantages and limitations of these methods as well as perspectives in COVID-19 diagnostics. The effort is constantly focused on understanding the quickly changing landscape of available diagnostic testing of COVID-19 at the clinical levels and introducing reliable and rapid screening point of care testing. The...

Background

Successful point-of-care testing, namely ensuring the completion of the test and treat cycle in the same encounter, has immense potential to reduce diagnostic and treatment delays, and impact patient outcomes. However, having rapid tests is not enough, as many barriers may prevent their successful implementation in point-of-care testing programs. Qualitative research on diagnostic practices may help identify such barriers across different points of care in health systems.

Methods

In this exploratory qualitative study, we conducted 78 semi-structured interviews and 13 focus group discussions in an urban and rural area of Karnataka, India, with healthcare providers (doctors, nurses, specialists, traditional healers, and informal providers), patients, community health workers, test manufacturers, laboratory technicians, program managers and policy-makers. Participants were purposively sampled to represent settings of hospitals, peripheral labs, clinics, communities and homes, in both the public and private sectors.

Results

In the Indian context, the onus is on the patient to ensure successful point-of-care testing across homes, clinics, labs and hospitals, amidst uncoordinated providers with divergent and often competing practices, in settings lacking material, money and human resources. We identified three overarching themes affecting point-of-care testing: the main theme is ‘relationships’ among providers and between providers and patients, influenced by the cross-cutting theme of ‘infrastructure’. Challenges with both result in ‘modified practices’ often favouring empirical (symptomatic) treatment over treatment guided by testing.

Conclusions

Even if tests can be conducted on the spot and infrastructure challenges have been resolved, relationships among providers and between patients and providers are crucial for successful point-of-care testing. Furthermore, these barriers do not act in isolation, but are interlinked and need to be examined as such. Also, a test alone has only limited power to overcome those difficulties. Test developers, policy-makers, healthcare providers and funders need to use these insights in overcoming barriers to point-of-care testing programs.

Background: Enoxaparin is increasingly used for the anticoagulation of patients undergoing percutaneous coronary intervention (PCI). Several reports have suggested the utility of using point of care tests in monitoring the anticoagulation levels of enoxaparin in patients undergoing PCI. The objective of this study was to evaluate a new point-of-care test (POCT) HEMONOX™ in monitoring the anticoagulant effect of enoxaparin in non citrated fresh whole blood samples from patients undergoing elective PCI procedure. Methods: Following IRB approval, blood samples were obtained from fifty-four patients who received two sequential intravenous doses of enoxaparin; 0.1 mg/kg followed 5 min later by 0.4 mg/kg for a total of 0.5 mg/kg. Blood was drawn at baseline and at 5, 10, 30 and 60 min post first bolus for evaluation in the clot-based POCT HEMONOX, ACT and aPTT and the chromogenic anti-Xa activity assay. Results: HEMONOX clotting time (CT) at baseline was 62.6 ± 6.2 secs, (n = 32) in healthy donors and statistically higher in PCI patients (71.6 ± 9.1 secs, p = 0.0001). The peak HEMONOX response that was always achieved at 10 min post bolus was >100 secs in all 54 patients, of these 83% yielded CT >150 secs (range: 150–466). There was no detectable anti-Xa activity level at baseline while peak HEMONOX CT corresponded to therapeutic levels (0.85 ± 0.14 U/ml; range: 0.61–1.34). Both HEMONOX CT and anti-Xa level significantly decreased at the time of sheath removal. HEMONOX CT at peak response suggested 3 patient subgroups with different levels of sensitivity to enoxaparin: low, intermediate and high responders. The correlation between anti-Xa activity level and HEMONOX CT was ≥0.85 in each patient subgroup when data from the 3 critical time points; baseline (absence of drug), peak response (10 min post bolus) and sheath removal (60 min post bolus) were analyzed. The correlation diminished to ≥0.83 when the analyses included data from all 5 time points [baseline, 5, 10, 30, and 60 min post bolus]. The HEMONOX test was the most sensitive POCT to measure the anticoagulant effects of enoxaparin. All patients completed PCI successfully. Conclusion: The HEMONOX test may be able to guide anticoagulation with enoxaparin during PCI. The HEMONOX assay is a one step whole blood coagulation test performed on the HEMOCHRON® Jr. Signature + POC system. The method was evaluated to monitor the anticoagulant level of enoxaparin in blood samples from patients undergoing PCI after receiving an intravenous dose of 0.5 mg/kg. The results suggest a clear distinction of HEMONOX CT between the baseline value of untreated patients and patients achieving therapeutic enoxaparin levels.

Introduction: Based on the existing studies, measuring serum level of immunoglobulin for making decisions regarding prescription of tetanus prophylaxis seems logical and cost effective. Therefore, the present study was done with the aim of evaluating the diagnostic accuracy of tetanus quick stick (TQS) in comparison with ELISA method in this regard.

Methods: The present diagnostic accuracy study was carried out on trauma patients presenting to emergency department, who were in need of receiving tetanus prophylaxis due to dirty wounds or injuries. Patients’ blood was evaluated regarding presence of anti-tetanus antibody via TQS and ELISA methods and screening performance characteristics of TQS in identifying the cases in need of receiving prophylaxis was calculated compared to ELISA as the reference test.

Results: 148 patients with the mean age of 34.58 ± 15.86 years (4-86) were studied (87.8% male). Agreement rate between the results of TQS and ELISA was 0.78 based on calculation of kappa coefficient. Sensitivity, specificity and area under the ROC curve of TQS were estimated to be 100 (95% CI: 96.50 – 100), 66.66 (95% CI: 38.68 – 86.01), and 0.83 (95% CI: 0.68 – 0.98), respectively. If TQS was used, the cost of treatment regarding use of tetabulin could have a 91.7% reduction.

Conclusion: Based on the findings of the present study, TQS has good diagnostic accuracy in comparison with ELISA and considering its 100% sensitivity and negative predictive value in cases with dirty wound, it can be considered as a reliable tool for screening patients that do not need to receive anti-tetanus prophylaxis.