Standard Venipuncture vs a Capillary Blood Collection Device for the Prospective Determination of Abnormal Liver Chemistry

Evaluation of a Novel Capillary Blood Collection System for Blood Sampling in Nontraditional Settings as Compared with Currently Marketed Capillary and Venous Blood Collection Systems for Selected General Chemistry Analytes

BACKGROUND

Nontraditional sites for blood collection, including retail pharmacies, can expand access to laboratory testing. Three studies assessed the BD® MiniDraw™ Capillary Blood Collection System (BD MiniDraw) along with the BD MiniDraw SST™ Capillary Blood Collection Tube (BD MiniDraw SST tube). This system allows trained healthcare workers to collect capillary blood without requiring phlebotomy experience, in accordance with state laws.

METHODS

Studies 1 and 2 evaluated clinical equivalence for selected serum chemistry analytes in the BD MiniDraw compared with currently marketed capillary and venous comparators. Study 3 evaluated within-tube stability for selected analytes up to 48 h in BD MiniDraw SST tubes following storage (2°-8°C). Contrived specimens were prepared to cover medically relevant ranges. Testing was performed on one general chemistry core laboratory analyzer in each study. Clinical equivalence was demonstrated if the biases and 95% limits were within a predefined clinical acceptance limit at all medical decision levels and time points for stability.

RESULTS

Clinical equivalence was demonstrated for all analytes for BD MiniDraw vs capillary and venous comparators except alanine aminotransferase and chloride for the venous comparator in study 1. Both showed clinical equivalence at the upper limit of the reference range; the confidence interval exceeded the clinical acceptance limit at the lower limit. Within-tube stability was demonstrated in BD MiniDraw SST tubes up to 48 h for all selected analytes.

CONCLUSIONS

The BD MiniDraw presents an option for blood collection in nontraditional settings that is clinically equivalent to conventional capillary and venous collection for the specified analytes.

Validation of a Reusable, Thermally Protective Specimen Shipper for Decentralized Sample Collections

BACKGROUND

The proliferation of decentralized sample collection models improves patient access and experience with laboratory medicine. However, many analytes have limited stability in liquid whole blood, serum, or plasma such that prompt transport under controlled temperature protection is crucial to analytical accuracy. Here we validate the Labcorp TrueTherm™ reusable shipper intended to thermally protect small volume specimens.

METHODS

Various TrueTherm shipper models were configured using stainless steel vacuum bottles, rigid phase change material (PCM) packs, and foam stoppers. A series of bench and real-world trans-US shipping studies were performed to evaluate thermal endurance against frozen, refrigerated, room temperature, and incubated temperature allowance criteria under summer and winter exposure conditions. Analytical utility was assessed by measuring 25 serum-based clinical chemistry markers using Roche cobas® 8000 analyzers following shipment in microvolume containers centrifuged or uncentrifuged and using various shipping methods. Additional studies evaluated the effect of centrifugation and thermal exposures on specimens exposed to ISTA-7D summer and winter shipping profiles.

RESULTS

The TrueTherm shipper exceeded 72-hour thermal endurance for most targeted applications when subjected to standard shipping validation thermal profiles. In real-world shipping studies, TrueTherm shippers paired with sample centrifugation prior to transport enabled most chemistry analytes to be measured with pair-wise comparisons within 2024 CLIA acceptance limits. Microsample hemolysis measurements showed that without centrifugation and thermal protection, average hemolysis levels fell well above maximum-allowable thresholds for laboratory analyzers.

CONCLUSION

The TrueTherm shipper provides a simple, effective, and reusable method for ensuring thermally protected shipment of small volume samples into centralized laboratories.

Comparing Venous vs. Capillary Blood Collection Methods for Proteomic Measurement in Peripheral Blood

BACKGROUND

Capillary blood collection has a number of advantages over venous collection, especially in the context of increasing decentralized clinical trials and field-based testing. No studies are available comparing venous versus capillary blood collection for proteomics measurement. The aim of this study was to compare venous versus capillary blood collection methods for proteomic measurement in peripheral blood.

METHODS

The expression of 368 different proteins from the Olink Explore 384 Inflammation panel was measured in both venous and capillary blood samples collected from 22 individuals at a single time point. Protein levels from venous and capillary blood samples were compared with descriptive statistics and correlation calculations. Correlations were examined for a subset of proteins identified in recent reports as associated with morbidity and mortality.

RESULTS

Strong positive correlation (r ≥ 0.7) between protein concentrations measured in venous and capillary blood samples was observed for two in three proteins tested (215 of 327, 66%). A further 47 (14%) showed a moderate positive correlation (0.4 ≤ r < 0.7), with weak or very weak correlation (r < 0.4) observed for the remaining 65 (20%). Protein expression was consistently higher in capillary blood samples for proteins with lower correlation (r < 0.6) between sampling methods. Further work is required to understand the underlying reasons why proteins were consistently under-expressed in venous samples/over-expressed in capillary samples in a minority of proteins tested.

CONCLUSIONS

Proteomic measurement utilising capillary blood collection provides very similar results to using venous blood collection. This is a promising sign for the validity and reliability of studies using capillary blood collection, including decentralised and remote studies.

Total Prostate-Specific Antigen (PSA) Testing in Capillary Samples: Proof-of-Principle and Feasibility Study for Home Self-Testing for Prostate Cancer

BACKGROUND

There is growing interest in the use of capillary blood sampling (CBS) for testing biochemical analytes owing to the advantages it offers including home surveillance of chronic conditions. In this study, we aimed to determine whether the use of CBS was a viable and feasible method for testing total prostate-specific antigen (TPSA) concentrations in men with prostate disease.

METHODS

Men with known prostate disease were recruited from a urology clinic where they were being treated or followed up. Samples were collected in serum separating tubes by the finger-prick method using validated devices. Simultaneously, venous blood was collected by venipuncture. We used validated immunoassays on both the Roche (Cobas 801) and Beckman (DXi) platforms to measure TPSA.

RESULTS

In total, 66 adult men between 26 and 64 years of age were tested. Across the concentration range of normal (0.3 µg/L) to pathological (314 µg/L), the results between CBS and venous samples were highly comparable and correlated (r = 0.997). The average bias was 0.112 µg/L or 1.07% and was not significant (P = 0.274). Overall, there was no apparent proportional or constant bias observed. Our data showed that TPSA may be stable in CBS stored at ambient temperature for up to 8 days in the samples tested using either the Roche or Beckman assays.

CONCLUSIONS

This feasibility study shows that CBS and venous samples are highly correlated and there was negligible bias. Further validation work is now required for the measurement of TPSA in CBS and determining outcomes in men with prostate disease.

Comparison of the capillary and venous blood plasma lipidomes: validation of self-collected blood for plasma lipidomics

Venipuncture of the upper extremities is commonly used to collect blood for plasma lipidomics. However, self-administered blood collection devices such as the Tasso+™ system for capillary blood sampling and plasma separation are convenient and enable frequent sampling without a clinical blood draw. The purpose of this study is to validate Tasso+ sampling for plasma lipidomics by comparing the venous blood and Tasso+-sampled capillary blood plasma lipidomes. Lipids are proven or putative biomarkers of human health and disease and indicators of nutritional and toxicological status. Because exchange of blood components including lipids occurs in capillaries, the capillary and venous blood lipidomes might be different, which could confound use of Tasso+-sampled blood as a surrogate for venous blood plasma. Here we compared the lipidomes of Tasso+-drawn capillary blood plasma and venous blood plasma in 10 male subjects using high-resolution mass spectrometry-based lipidomics. While there was substantial interindividual variability between lipidomes, comprehensive statistical approaches with cross-validation and multiple testing adjustments showed no difference (adjusted P-value > 0.05) in lipid composition of the paired blood samples. A linear regression model with Spearman correlation analysis also showed a significant-to-near-perfect level (r = 0.95-0.99) of concordance between the samples. Aside from monoacylglycerols and cardiolipins, every class of lipid was strongly correlated (r = 0.9-0.99) between paired venous and capillary blood plasma. In summary, the capillary and venous blood plasma lipidomes are essentially identical making self-administered collection of capillary blood a viable approach for clinical blood plasma lipidomics.

Quantifying sampling method-induced imprecision in user-friendly lateral upper arm blood collection: Introducing σ3-methodology (S3) for the verification of alternative sampling methods with TAP® II as a use case

BACKGROUND

Alternative means of blood sampling continue to grow due to the scarcity of phlebotomists and the need for person-centered care. It is crucial to consistently support these alternative blood sampling innovations with scientific evidence to guarantee the quality of care, especially when implementing for instance Lateral Upper-arm Blood Collection (LUBC) for use at home. Knowledge gaps remain in how to quantify imprecision introduced by the collection method and its impact on clinical use.

METHODS

We developed the Six Sigma analysis for alternative Sampling methods, including sampling method-induced imprecision, accuracy and precision, called σ3-methodology (S3). We performed a two-step verification using σ3-methodology for LUBC TAP® II, which included fourteen routine clinical analytes. We used venipuncture as the gold standard.

RESULTS

The biggest source of imprecision for all analytes was sampling method-induced imprecision, which, for the first time, was quantified, resulting in a varying effect on the clinical usability. TAP® II showed acceptable analytical performance for ALP, bilirubin, HDL-cholesterol, CRP and sodium. Unacceptable analytical performance was found for ALT, AST, cholesterol, creatinine, GGT, HbA1c, potassium, LDH and triglycerides.

CONCLUSION

Alternative blood sampling innovations hold promise for advancing diagnostic care, aiming to deliver accessible decentralised sample collection at home that does not require phlebotomist involvement. However, sampling method-induced imprecision should not be overlooked in the performance assessment to guarantee responsible development that will contribute to the success and desirable societal impact of alternative sampling technologies.

Blood self-sampling devices: innovation, interpretation and implementation in total lab automation

The introduction of the vacuum tube in 1949 revolutionized blood collection, significantly improving sample quality and patient comfort. Over the past 75 years, laboratory diagnostics have evolved drastically, from manual to automated processes, reducing required test volumes by over 1,000 times. Despite these advancements, venous blood collection presents logistical challenges, including centralized scheduling and a large volume of biological waste due to the imbalance between the needed blood volume (often very little) and the collected volume (often in excess). The COVID-19 pandemic further emphasized the need for decentralized healthcare solutions and patient empowerment. Capillary blood collection, widely used in point-of-care testing, offers a promising alternative, particularly for patients facing frequently, or difficulties with, venous sampling. The Leiden University Medical Center in the Netherlands experienced a 15 % reduction in volume of laboratory tests during and after the pandemic, attributed to patient preference for local blood collection and testing. To address these challenges, self-sampling devices are emerging, empowering patients and streamlining sample logistics. However, challenges such as cost, transportation regulations, and sample volume adequacy persists. Robust devices tailored for total lab automation and sustainable practices are crucial for widespread adoption. Despite hurdles, the integration of self-sampling into diagnostic processes is inevitable, heralding a shift towards patient-centered, proactive healthcare. Practical recommendations include robust device design, ease of use, affordability, sustainability, sufficient quality and acceptability by seamless integration into laboratory workflows. Although obstacles remain, self-sampling represents the future of laboratory diagnostics, offering convenience, cost-effectiveness, interoperability and patient empowerment.

Use of dried blood spots in the detection of coronavirus disease 2019 (COVID-19): A systematic review

INTRODUCTION

COVID-19 disease continues to be a global health concern. The current protocol for detecting SARS-CoV-2 requires healthcare professionals to draw blood from patients. Recent studies showed that dried blood spot (DBS) is a valuable sampling procedure that can collect a low blood volume without the need for the presence of medical practitioners. This study synthesized the available literature on using DBS as a blood collection tool to diagnose COVID-19 disease.

MATERIALS AND METHODS

A comprehensive search utilizing OVID, CINAHL, and Scopus databases was done from inception to March 2023. Five reviewers collected, extracted and organized the study data.

RESULTS

This systematic review included 57 articles. DBS was commonly prepared by finger pricking. Most studies showed more favorable results and longer sample stability (more than 1080 days) with lower storage temperature conditions for the DBS. DBS samples were mostly used for serological assays for COVID-19 disease detection. ELISA was the most used detection method (43.66 %). Diagnostic performance of laboratory tests for COVID-19 using DBS sample showed high sensitivity of up to 100 % for immunoassay tests and 100 % specificity in agglutination, PCR, and DELFIA assays.

CONCLUSION

DBS sampling coupled with serological testing can be an alternative method for collecting blood and detecting COVID-19 disease. These tests using DBS samples showed excellent diagnostic performance across various geographic locations and demographics.

Evaluation of Patient-Centric Sample Collection Technologies for Pharmacokinetic Assessment of Large and Small Molecules

Low-volume sampling devices offer the promise of lower discomfort and greater convenience for patients, potentially reducing patient burden and enabling decentralized clinical trials. In this study, we determined whether low-volume sampling devices produce pharmacokinetic (PK) data comparable to conventional venipuncture for a diverse set of monoclonal antibodies (mAbs) and small molecules. We adopted an open-label, non-randomized, parallel-group, single-site study design, with four cohorts of 10 healthy subjects per arm. The study drugs, doses, and routes of administration included: crenezumab (15 mg/kg, intravenous infusion), etrolizumab (210 mg, subcutaneous), GDC-X (oral), and hydroxychloroquine (HCQ, 200 mg, oral). Samples were collected after administration of a single dose of each drug using conventional venipuncture and three low-volume capillary devices: TassoOne Plus for liquid blood, Tasso-M20 for dry blood, both applied to the arm, and Neoteryx Mitra® for dry blood obtained from fingertips. Serum/plasma concentrations from venipuncture and TassoOne Plus samples overlapped and PK parameters were comparable for all drugs, except HCQ. After applying a baseline hematocrit value, the dry blood concentrations and PK parameters for the two monoclonal antibodies were comparable to those obtained from venipuncture. For the two small molecules, two bridging strategies were evaluated for converting dry blood concentrations to equivalent plasma concentrations. A baseline hematocrit correction and/or linear regression-based correction was effective for GDC-X, but not for HCQ. Additionally, the study evaluated the bioanalytical data quality and comparability from the various collection methods, as well as patient preference for the devices.

Proof-of-concept study: Remote capillary blood collection for hCG analysis in early pregnancy

INTRODUCTION

Capillary blood collection, a technique traditionally used in diabetes care, shows promise for many applications including pregnancy monitoring. Serial measurement of serum human Chorionic Gonadotrophin (hCG) is frequently necessary for managing early pregnancy, including molar pregnancy, requiring multiple visits to a maternity hospital for blood collection by venepuncture. This proof-of-concept study aimed to assess the clinical performance and user acceptability of capillary blood samples collected remotely, as an alternative to venous blood for hCG measurement.

METHODS

Women attending the early pregnancy unit who required serum hCG measurement, were invited to participate. Following informed written consent, participants were shown how to collect capillary blood samples using the Mini-Collect® collection device. Matched venous and capillary blood samples were collected in clinic for hCG comparison purposes. Participants were also supplied with a home collection kit in a prepaid return envelope. They were asked to perform a finger-prick blood collection at home using the instructions provided and to return the capillary blood sample by post within 24 h of collection, along with a completed user-satisfaction questionnaire. Statistical analysis was performed using Analyse-it® software.

RESULTS

The study enrolled 71 participants and over a third of these women collected a capillary blood sample at home. The median age of participants was 33 years (range 29-36). Passing-Bablok linear regression (y = -0.037 + 1.04x) and Spearman correlation (r = 0.999, p < 0.0001), demonstrated good agreement and strong correlation between venous and capillary samples, over a broad range of hCG values (1.2 to 224,0000 IU/L). The majority of capillary samples collected remotely (39%, 27/69) had sufficient blood volume for analysis (74%, 20/27). Respondents (77%, 18/25) found the collection device easy to use and expressed willingness to use a future service if available (80%, 20/25) CONCLUSION: The study demonstrated excellent agreement between the hCG results obtained from both collection methods, suggesting that capillary blood can serve as a reliable alternative for venous hCG measurement, particularly in clinical settings requiring frequent hCG monitoring. Feedback from the study questionnaire indicates a preference for this type of follow-up among women, indicating potential improvements in compliance for blood based diagnostic tests.

Micro blood analysis technology (μBAT): multiplexed analysis of neutrophil phenotype and function from microliter whole blood samples

There is an ongoing need to do more with less and provide highly multiplexed analysis from limited sample volumes. Improved "sample sparing" assays would have a broad impact across pediatric and other rare sample type studies in addition to enabling sequential sampling. This capability would advance both clinical and basic research applications. Here we report the micro blood analysis technology (μBAT), a microfluidic platform that supports multiplexed analysis of neutrophils from a single drop of blood. We demonstrate the multiplexed orthogonal capabilities of μBAT including functional assays (phagocytosis, neutrophil extracellular traps, optical metabolic imaging) and molecular assays (gene expression, cytokine secretion). Importantly we validate our microscale platform using a macroscale benchmark assay. μBAT is compatible with lancet puncture or microdraw devices, and its design facilitates rapid operations without the need for specialized equipment. μBAT offers a new method for investigating neutrophil function in populations with restricted sample amounts.

Decentralized Clinical Trials in Early Drug Development-A Framework Proposal

The COVID-19 pandemic has led to a rethinking of clinical trial design to maintain clinical research activity, with regulatory changes allowing for the wider implementation and development of decentralized design models. Evidence of the feasibility and benefits associated with a remote design comes mainly from observational studies or phase 2 and 3 clinical trials, in which implementation is easier with a better-established safety profile. Early drug development is a slow and expensive process in which accrual and safety are key aspects of success. Applying a decentralized model to phase 1 clinical trials could improve patient accrual by removing geographic barriers, improving patient population diversity, strengthening evidence for rare tumors, and reducing patients' financial and logistical burdens. However, safety monitoring, data quality, shipment, and administration of the investigational product are challenges to its implementation. Based on published data for decentralized clinical trials, we propose an exploratory framework of solutions to enable the conceptualization of a decentralized model for phase 1 clinical trials.

Capillary blood self-collection for high-throughput proteomics

In this study, we sought to compare protein concentrations obtained from a high-throughput proteomics platform (Olink) on samples collected using capillary blood self-collection (with the Tasso+ device) versus standard venipuncture (control). Blood collection was performed on 20 volunteers, including one sample obtained via venipuncture and two via capillary blood using the Tasso+ device. Tasso+ samples were stored at 2°C-8°C for 24-hs (Tasso-24) or 48-h (Tasso-48) prior to processing to simulate shipping times from a study participant's home. Proteomics were analyzed using Olink (384 Inflammatory Panel). Tasso+ blood collection was successful in 37/40 attempts. Of 230 proteins included in our analysis, Pearson correlations (r) and mean coefficient of variation (CV) between Tasso-24 or Tasso-48 versus venipuncture were variable. In the Tasso-24 analysis, 34 proteins (14.8%) had both a correlation r > 0.5 and CV < 0.20. In the Tasso-48 analysis, 68 proteins (29.6%) had a correlation r > 0.5 and CV < 0.20. Combining the Tasso-24 and Tasso-48 analyses, 26 (11.3%) proteins met these thresholds. We concluded that protein concentrations from Tasso+ samples processed 24-48 h after collection demonstrated wide technical variability and variable correlation with a venipuncture gold-standard. Use of home capillary blood self-collection for large-scale proteomics should be limited to select proteins with good agreement with venipuncture.

Late cytomegalovirus disease after hematopoietic cell transplantation: significance of novel transplantation techniques

ABSTRACT

Preemptive therapy (PET) and letermovir prophylaxis are effective in preventing cytomegalovirus (CMV) disease within the first 100 days after allogeneic hematopoietic cell transplantation (HCT) but are associated with late-onset CMV disease. We retrospectively examined the clinical manifestations, risk factors, prevention algorithm, and outcome of late CMV disease in CMV seropositive day 100 survivors transplanted between 2001-2017 (PET cohort) and 2018-2021 (letermovir cohort). There were 203 episodes of late CMV disease among 2469 day 100 survivors, and the estimated cumulative incidence of first late CMV disease was 7.2% (95% confidence interval [CI], 6.2-8.3) with no difference between the PET (7.4%; 95% CI, 6.4-8.6) and the letermovir group (5.4%; 95% CI, 3.2-8.3). Thirty-seven patients (1.5%) had a second episode of CMV disease. In multivariable Cox regression models, posttransplant cyclophosphamide was associated with an increased risk of gastrointestinal CMV disease. CMV viremia or disease detected before day 100, corticosteroid treatment after day 100 at dose ≥1 mg/kg, acute and chronic graft-versus-host disease, lymphopenia, HLA-mismatched related donor status, were also associated with late CMV disease. HLA-mismatched donor status and late use of corticosteroids (≥1 mg/kg) were risk factors for late CMV disease recurrence. Late CMV disease occurred most frequently in a setting of prolonged low-level untreated viremia and was independently associated with death by 2 years after HCT. In summary, late CMV disease continues to occur in the present era. Improved prevention strategies for late CMV disease are needed.

Hospital at Home programs: Decentralized inpatient care but centralized laboratory testing?

The Hospital at Home (HaH) program has experienced accelerated growth in major Canadian provinces, driven in part by technological advancements and evolving patient needs during the COVID-19 pandemic. As an increasing number of hospitals pilot or implement these innovative programs, substantial resources have been allocated to support clinical teams. However, it is crucial to note that the vital roles played by clinical laboratories remain insufficiently acknowledged. This mini review aims to shed light on the diverse functions of clinical laboratories, spanning the preanalytical, analytical, and post-analytical phases within the HaH program context. Additionally, the review will explore recent advancements in clinical testing and the potential benefits of integrating new technologies into the HaH framework. Emphasizing the integral role of clinical laboratories, the discussion will address the current barriers hindering their active involvement, accompanied by proposed solutions. The capacity and efficiency of the HaH program hinge on sustained collaborative efforts from various teams, with clinical laboratories as crucial team players. Recognizing and addressing the specific challenges faced by clinical laboratories is essential for optimizing the overall performance and impact of the HaH initiative.

Feasibility, acceptability, and safety of a novel device for self-collecting capillary blood samples in clinical trials in the context of the pandemic and beyond

BACKGROUND

Home blood self-collection devices can enable remote monitoring, but their implementation requires validation. Our objectives were to explore (i) the impact of sampling sites and topical analgesia on capillary blood volume and pain perception and (ii) the safety, acceptability, and failure of capillary self-collection among adults and children using the Tasso-SST device.

METHODS

We conducted a two-phase study. The investigational phase consisted of two on-site cross-sectional studies in healthy adult participants (≥ 12 years) and children (1-17 years) with their accompanying parent. Adults received 4 capillary samplings, where puncture sites and topical analgesia were randomized in a factorial design, and a venipuncture; children (and one parent) had one capillary sampling. The two co-primary outcomes were blood volume and pain. The implementation phase was conducted in two multicentre trials in participants choosing remote visits; blood volume, collection failure, adverse events, and satisfaction were documented.

RESULTS

In the investigational phase, 90 participants and 9 children with 7 parents were enrolled; 15 adults and 2 preschoolers participated in the implementation phase. In the adult investigational study, the device collected a median (25%, 75%) of 450 (250, 550) μl of blood with no significant difference between the puncture site, topical analgesia, and its interaction. Using topical analgesia reduced pain perception by 0.61 (95% CI: 0.97, 0.24; P <0.01) points on the 11-point scale; the pain reduction varied by puncture site, with the lower back showing the most significant decrease. Overall, combining all studies and phases, the median volume collected was 425 (250, 500) μl, and the device failure rate was 4.4%; minor adverse effects were reported in 8.9% of the participants, all were willing to use the device again.

CONCLUSION

Capillary blood self-collection, yielding slightly less than 500 μl, proves to be a safe and relatively painless method for adults and children, with high satisfaction and low failure rates. The puncture site and topical analgesia do not affect blood volume, but topical analgesia on the lower back could reduce pain.

Enhancing drug development and clinical studies with patient-centric sampling using microsampling techniques: Opportunities, challenges, and insights into liquid chromatography-mass spectrometry strategies

Microsampling has revolutionized pharmaceutical drug development and clinical research by reducing sample volume requirements, allowing sample collection at home or nontraditional sites, minimizing animal and patient burden, and enabling more flexible study designs. This perspective paper discusses the transformative impact of microsampling and patient-centric sampling (PCS) techniques, emphasizing their advantages in drug development and clinical trials. We highlight the integration of liquid chromatography-mass spectrometry (LC-MS) strategies for analyzing PCS samples, focusing on our research experience and a review of current literatures. The paper reviews commercially available PCS devices, their regulatory status, and their application in clinical trials, underscoring the benefits of PCS in expanding patient enrollment diversity and improving study designs. We also address the operational challenges of implementing PCS, including the need for bridging studies to ensure data comparability between traditional and microsampling methods, and the analytical challenges posed by PCS samples. The paper proposes future directions for PCS, including the development of global regulatory standards, technological advancements to enhance user experience, the increased concern of sustainability and patient data privacy, and the integration of PCS with other technologies for improved performance in drug development and clinical studies. By advancing microsampling and PCS techniques, we aim to foster patient-centric approaches in pharmaceutical sciences, ultimately enhancing patient care and treatment efficacy.

Optimizing the data in direct access testing: information technology to support an emerging care model

Direct access testing (DAT) is an emerging care model that provides on-demand laboratory services for certain preventative, diagnostic, and monitoring indications. Unlike conventional testing models where health care providers order tests and where sample collection is performed onsite at the clinic or laboratory, most interactions between DAT consumers and the laboratory are virtual. Tests are ordered and results delivered online, and specimens are frequently self-collected at home with virtual support. Thus, DAT depends on high-quality information technology (IT) tools and optimized data utilization to a greater degree than conventional laboratory testing. This review critically discusses the United States DAT landscape in relation to IT to highlight digital challenges and opportunities for consumers, health care systems, providers, and laboratories. DAT offers consumers increased autonomy over the testing experience, cost, and data sharing, but the current capacity to integrate DAT as a care option into the conventional patient-provider model is lacking and will require innovative approaches to accommodate. Likewise, both consumers and health care providers need transparent information about the quality of DAT laboratories and clinical decision support to optimize appropriate use of DAT as a part of comprehensive care. Interoperability barriers will require intentional approaches to integrating DAT-derived data into the electronic health records of health systems nationally. This includes ensuring the laboratory results are appropriately captured for downstream data analytic pipelines that are used to satisfy population health and research needs. Despite the data- and IT-related challenges for widespread incorporation of DAT into routine health care, DAT has the potential to improve health equity by providing versatile, discreet, and affordable testing options for patients who have been marginalized by the current limitations of health care delivery in the United States.

Determination of Capillary Blood TSH and Free Thyroxine Levels Using Digital Immunoassay

Background

The remote performance of thyroid function blood tests is complicated because it requires blood collection.

Objective

To compare TSH and free thyroxine (FT4) levels between capillary and venous blood and assess the adequacy of measuring each value in capillary blood.

Methods

This prospective intervention study was conducted at Ito Hospital and was based on the clinical research method. The participants were 5 healthy female volunteers and 50 patients (41 females and 9 males) between the ages of 23 and 81 years. To measure TSH and FT4 levels in capillary and venous blood, a digital immunoassay (d-IA) method capable of measuring trace samples was used. Chemiluminescence measurements were used as controls. Values obtained for each assay system were compared using Spearman's correlation analysis. Capillary blood was collected using an autologous device (TAP II; not approved in Japan).

Results

Capillary plasma volume obtained using TAP II was 125 µL or more in 26 cases, 25 µL to 124 µL in 24 cases, and less than 25 µL in 5 cases. Strong correlations were noted in the TSH and FT4 levels between capillary and venous blood, with correlation coefficients of rs = 0.99 and rs = 0.97, respectively.

Conclusion

Capillary TSH and FT4 levels strongly correlate with venous blood values. Trace samples can be used in high-precision d-IA methods. These results may promote telemedicine in assessing thyroid function.

Transdermal Blood Sampling for C-Peptide Is a Minimally Invasive, Reliable Alternative to Venous Sampling in Children and Adults With Type 1 Diabetes

OBJECTIVE

C-peptide and islet autoantibodies are key type 1 diabetes biomarkers, typically requiring venous sampling, which limits their utility. We assessed transdermal capillary blood (TCB) collection as a practical alternative.

RESEARCH DESIGN AND METHODS

Ninety-one individuals (71 with type 1 diabetes, 20 control; individuals with type 1 diabetes: aged median 14.8 years [interquartile range (IQR) 9.1-17.1], diabetes duration 4.0 years [1.5-7.7]; control individuals: 42.2 years [38.0-52.1]) underwent contemporaneous venous and TCB sampling for measurement of plasma C-peptide. Participants with type 1 diabetes also provided venous serum and plasma, and TCB plasma for measurement of autoantibodies to glutamate decarboxylase, islet antigen-2, and zinc transporter 8. The ability of TCB plasma to detect significant endogenous insulin secretion (venous C-peptide ≥200 pmol/L) was compared along with agreement in levels, using Bland-Altman. Venous serum was compared with venous and TCB plasma for detection of autoantibodies, using established thresholds. Acceptability was assessed by age-appropriate questionnaire.

RESULTS

Transdermal sampling took a mean of 2.35 min (SD 1.49). Median sample volume was 50 µL (IQR 40-50) with 3 of 91 (3.3%) failures, and 13 of 88 (14.7%) <35 µL. TCB C-peptide showed good agreement with venous plasma (mean venous ln[C-peptide] - TCB ln[C-peptide] = 0.008, 95% CI [-0.23, 0.29], with 100% [36 of 36] sensitivity/100% [50 of 50] specificity to detect venous C-peptide ≥200 pmol/L). Where venous serum in multiple autoantibody positive TCB plasma agreed in 22 of 32 (sensitivity 69%), comparative specificity was 35 of 36 (97%). TCB was preferred to venous sampling (type 1 diabetes: 63% vs. 7%; 30% undecided).

CONCLUSIONS

Transdermal capillary testing for C-peptide is a sensitive, specific, and acceptable alternative to venous sampling; TCB sampling for islet autoantibodies needs further assessment.

Self-sampling of blood using a topper and pediatric tubes; a prospective feasibility study for PSA analysis using 120 prostate cancer patients

OBJECTIVES

Self-collection of blood for diagnostic purposes by blood collection assist devices (BCAD) has gained a lot of momentum. Nonetheless, there are a lack of studies demonstrating the feasibility and reliability of self-collecting capillary blood for routine (immuno)chemistry testing. In this study we describe the topper technology together with pediatric tubes to enable self-collection of blood and investigated its feasibility for PSA testing by prostate cancer patients.

METHODS

A total of 120 prostate cancer patients for which a routine follow-up PSA test was requested, were included in this study. Patients received instruction materials and the blood-collection device consisting of a topper, pediatric tube and base-part, and performed the blood collection procedure themselves. Afterwards a questionnaire was filled-in. Finally, PSA was measured on a Roche Cobas Pro.

RESULTS

The overall self-sampling success rate was 86.7 %. Furthermore, when specified per age category, a 94.7 % success rate for patients under 70 years and a 25 % success rate for patients of 80 years and older was observed. Venous and self-collected PSA were highly comparable when analyzed by Passing-Bablok regression with a slope of 0.99 and intercept of 0.00011, Spearmans correlation coefficient (0.998) and average self-collected PSA recovery of 99.8 %.

CONCLUSIONS

Evidence is presented that self-collected capillary blood by topper and pediatric tube from the finger is feasible, particularly for patients under 70 years. Furthermore, capillary blood self-sampling did not compromise any of the PSA test results. Future validation in a real-world setting, without supervision and including sample stability and logistics, is required.

Decentralized clinical trial design using blood microsampling technology for serum bioanalysis

Background: Alternatives to phlebotomy in clinical trials increase options for patients and clinicians by simplifying and increasing accessibility to clinical trials. The authors investigated the technical and logistical considerations of one technology compared with phlebotomy. Methodology: Paired samples were collected from 16 donors via a second-generation serum gel microsampling device and conventional phlebotomy. Microsamples were subject to alternative sample handling conditions and were evaluated for quality, clinical testing and proteome profiling. Results: Timely centrifugation of blood serum microsamples largely preserved analyte stability. Conclusion: Centrifugation timing of serum microsamples impacts the quality of specific clinical chemistry and protein biomarkers. Microsampling devices with remote centrifugation and refrigerated shipping can decrease patient burden, expand clinical trial populations and aid clinical decisions.

Whole blood cytokine release assays reveal disparity between capillary blood sampling methods

INTRODUCTION

The use of whole blood in rapid cytokine release assays (CRAs) is becoming an established technique for screening immune responses following natural infection or vaccination, especially in the context of the SARS-CoV-2 pandemic. Establishing an accurate capillary blood sampling method to replace the need for venipuncture could make CRAs more accessible. In this study, capillary blood was collected via two different methods alongside traditional venipuncture to investigate whether the method of blood draw affects cytokine quantification when performing CRAs.

METHODS

Adults previously vaccinated with SARS-CoV-2 vaccines donated three blood samples: one by venipuncture, one by finger prick, and one by a microneedle device. Whole blood was aliquoted and incubated overnight with SARS-CoV-2 peptides or left unstimulated. Cytokine release in plasma was measured by multiplex array.

RESULTS

In unstimulated samples, little to no cytokines were detected in blood collected via venipuncture or by microneedle devices. Conversely, capillary blood collected by finger prick showed detectable levels of all cytokines analysed, with significantly inflated levels of TNFα, IL-10 (p < 0.0001), IL-2, GM-CSF, and IL-13 (p < 0.01), and 53% of these samples were also positive for IFN-γ. Following peptide stimulation, 25% of samples collected via finger prick showed dysregulated production of IFN-γ, TNFα, IL-2, and IL-10, with lower cytokine production than unstimulated controls. Contrastingly, this was seen in just 4% of venous blood samples and in none of the microneedle samples.

CONCLUSIONS

Capillary blood draw via a microneedle device results in highly comparable immune responses to those seen via venipuncture at baseline and following peptide stimulation, suggesting this is a viable method for rapid whole blood CRAs. Conversely, differential cytokine production is observed following capillary blood draw via finger prick.

Capillary blood stability and analytical accuracy of 12 analytes stored in Microtainers®

Objectives

The aim of this study was to determine feasibility of collecting capillary blood by traditional fingerstick and next day analysis after transport in Microtainers® at ambient temperature with no plasma separation. This study is pursuing an acceptable alternative to venipuncture for measuring 12 analytes important for health risk assessment.

Design

and Methods: Performance standards of a 12-assay chemistry panel were assessed using a set of paralleled serum and capillary microsamples. The panel included Hemoglobin A1c (HbA1c), Total Cholesterol, Triglycerides, HDL-C, Creatinine, Urea Nitrogen (BUN), Uric Acid, alkaline phosphatase (ALP), ALT (GPT), AST (GOT), gamma-glutamyltransferase (GGT), and total protein. Correlation studies were performed using 31 simultaneous venous and capillary blood collections. Analytical bias, correlation, and medical decision points were calculated to determine equivalency of sample type and the impact of transport conditions. Clinical sensitivity, specificity, and predictive values were evaluated at calculated medical decision points for their usability in health screening initiatives.

Results

Laboratory test results using capillary blood samples stored in Microtainers® under conditions of delayed centrifugation, and mail transport at ambient temperature, showed an acceptable agreement with results obtained using their paired serum samples analyzed using standard methods, except AST.

Conclusions

Capillary blood samples can be self-collected at remote locations using Microtainers® and transported at ambient temperature for 24 h for successful performance of several medical tests important in large-scale health screenings programs.

Painless Capillary Blood Collection: A Rapid Evaluation of the Onflow Device

Blood-based diagnostics are critical for many medical decisions, but mostly rely on venepuncture, which can be inconvenient and painful. The Onflow Serum Gel (Loop Medical SA, Vaud, Lausanne, Switzerland) is a novel blood collection device that utilises needle-free technology to collect capillary blood. In this pilot study, 100 healthy participants were enrolled and provided two Onflow collected specimens and one venous blood specimen. Five chemistry analytes (AST, ALT, LDH, potassium, creatinine) and haemolysis were measured per specimen, and laboratory analyte results were compared. Onflow was found to be more acceptable than venepuncture with lower pain ratings, and 96.5% of participants would use the Onflow method again. All phlebotomists (100%) found Onflow intuitive and user-friendly, with ~1 mL of Onflow blood successfully collected from 99% of participants in <12 min (mean: 6 min, 40 s) and 91% collected on the first attempt. ALT and AST analytes showed no difference in performance, while creatinine generated a negative bias (-5.6 µmol/L), and increased variability was noted with potassium (3.6%CV) and LDH (6.7%CV), although none were clinically relevant. These differences may be due to 35% of Onflow collected specimens having "mild" haemolysis. Onflow is a promising alternative blood collection device that should now be evaluated in participants with expected abnormal chemistries and as an option for self-collection.