Self-sampling of capillary blood for serological testing of SARS-CoV-2 by COVID-19 IgG ELISA

Serological testing is emerging as a powerful tool to progress our understanding of COVID-19 exposure, transmission and immune response. Large-scale testing is limited by the need for in-person blood collection by staff trained in venepuncture. Capillary blood self-sampling and postage to laboratories for analysis could provide a reliable alternative. Two-hundred and nine matched venous and capillary blood samples were obtained from thirty nine participants and analysed using a COVID-19 IgG ELISA to detect antibodies against SARS-CoV-2. Thirty seven out of thirty eight participants were able to self-collect an adequate sample of capillary blood (≥50 μl). Using plasma from venous blood collected in lithium heparin as the reference standard, matched capillary blood samples, collected in lithium heparin-treated tubes and on filter paper as dried blood spots, achieved a Cohen′s kappa coefficient of >0.88 (near-perfect agreement). Storage of capillary blood at room temperature for up to 7 days post sampling did not affect concordance. Our results indicate that capillary blood self-sampling is a reliable and feasible alternative to venepuncture for serological assessment in COVID-19.

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Self-sampling of capillary blood for SARS-CoV-2 serology

Scientific Reports ◽

10.1038/s41598-021-86008-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lottie Brown ◽

Rachel L. Byrne ◽

Alice Fraser ◽

Sophie I. Owen ◽

Ana I. Cubas-Atienzar ◽

...

Keyword(s):

Large Scale ◽

Venous Blood ◽

Dried Blood Spots ◽

Capillary Blood ◽

Blood Collection ◽

Perfect Agreement ◽

Blood Samples ◽

Large Scale Testing ◽

Feasible Alternative ◽

Lateral Flow Tests

AbstractSerological testing is emerging as a powerful tool to progress our understanding of COVID-19 exposure, transmission and immune response. Large-scale testing is limited by the need for in-person blood collection by staff trained in venepuncture, and the limited sensitivity of lateral flow tests. Capillary blood self-sampling and postage to laboratories for analysis could provide a reliable alternative. Two-hundred and nine matched venous and capillary blood samples were obtained from thirty nine participants and analysed using a COVID-19 IgG ELISA to detect antibodies against SARS-CoV-2. Thirty eight out of thirty nine participants were able to self-collect an adequate sample of capillary blood (≥ 50 µl). Using plasma from venous blood collected in lithium heparin as the reference standard, matched capillary blood samples, collected in lithium heparin-treated tubes and on filter paper as dried blood spots, achieved a Cohen’s kappa coefficient of > 0.88 (near-perfect agreement, 95% CI 0.738–1.000). Storage of capillary blood at room temperature for up to 7 days post sampling did not affect concordance. Our results indicate that capillary blood self-sampling is a reliable and feasible alternative to venepuncture for serological assessment in COVID-19.

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Potential of Dried Blood Self-Sampling for CyclosporineC2Monitoring in Transplant Outpatients

Journal of Transplantation ◽

10.1155/2010/201918 ◽

2010 ◽

Vol 2010 ◽

pp. 1-6 ◽

Cited By ~ 15

Author(s):

Alexander Benedikt Leichtle ◽

Uta Ceglarek ◽

Helmut Witzigmann ◽

Gábor Gäbel ◽

Joachim Thiery ◽

...

Keyword(s):

Therapeutic Drug Monitoring ◽

Venous Blood ◽

Dried Blood Spots ◽

Capillary Blood ◽

Blood Sampling ◽

Therapeutic Drug ◽

Blood Collection ◽

Blood Samples ◽

Drug Levels ◽

Finger Prick

Background. Close therapeutic drug monitoring of Cyclosporine (CsA) in transplant outpatients is a favourable procedure to maintain the long-term blood drug levels within their respective narrow therapeutic ranges. Compared to basal levels (C0), CsA peak levels (C2) are more predictive for transplant rejection. However, the application ofC2levels is hampered by the precise time of blood sampling and the need of qualified personnel. Therefore, we evaluated a newC2self-obtained blood sampling in transplant outpatients using dried capillary and venous blood samples and compared the CsA levels, stability, and clinical practicability of the different procedures.Methods. 55 solid organ transplant recipients were instructed to use single-handed sampling of each 50μL capillary blood and dried blood spots by finger prick using standard finger prick devices. We used standardized EDTA-coated capillary blood collection systems and standardized filter paper WS 903. CsA was determined by LC-MS/MS. The patients and technicians also answered a questionnaire on the procedure and sample quality.Results. TheC0andC2levels from capillary blood collection systems (C0[ng/mL]:114.5±44.5;C2:578.2±222.2) and capillary dried blood (C0[ng/mL]:175.4±137.7;C2:743.1±368.1) significantly(P<.01)correlated with the drug levels of the venous blood samples (C0[ng/mL]:97.8±37.4;C2:511.2±201.5). The correlation atC0wasρcap.-ven.= 0.749, andρdried blood-ven= 0.432; atC2: ρcap.-ven.= 0.861 andρdried blood-ven= 0.711. The patients preferred the dried blood sampling because of the more simple and less painful procedure. Additionally, the sample quality of self-obtained dried blood spots for LC-MS/MS analytics was superior to the respective capillary blood samples.Conclusions.C2self-obtained dried blood sampling can easily be performed by transplant outpatients and is therefore suitable and cost-effective for close therapeutic drug monitoring.

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An Assessment of Dried Blood-Spot Technology for Identifying Iron Deficiency

Blood ◽

10.1182/blood.v92.5.1807 ◽

1998 ◽

Vol 92 (5) ◽

pp. 1807-1813 ◽

Cited By ~ 38

Author(s):

James D. Cook ◽

Carol H. Flowers ◽

Barry S. Skikne

Keyword(s):

Iron Deficiency ◽

Transferrin Receptor ◽

Venous Blood ◽

Dried Blood Spots ◽

Epidemiologic Studies ◽

Capillary Blood ◽

Deficiency Anemia ◽

Blood Samples ◽

Blood Spots ◽

American Society

Abstract The present study was undertaken to assess the feasibility of using ferritin and transferrin receptor measurements on dried capillary blood spots to identify iron deficiency (ID) in public health surveys. Measurements on serum and blood spots prepared from venous blood were performed in 71 healthy subjects, 41 of whom were iron-replete and 30 who had ID, either without (n = 20) or with (n = 10) anemia. Parallel measurements were performed on hemolyzed whole blood and washed hemolyzed red blood cells to assess the erythrocyte contribution of ferritin and transferrin receptor to dried blood samples. The concentration of ferritin in dried blood samples was threefold higher than serum assays due to the release of ferritin from hemolyzed erythrocytes, which diminished the usefulness of ferritin measurements for detecting ID. On the other hand, there was negligible erythrocyte contribution to the measurement of transferrin receptor in dried blood spots. The most sensitive parameter in dried blood spots was the ratio of receptor/ferritin, which was suitable for identifying iron-deficiency anemia (IDA), but less reliable than serum assays for detecting milder ID without anemia. We conclude that tandem measurements of serum ferritin and transferrin receptor in dried blood spots can be used to facilitate the identification of IDA in epidemiologic studies. © 1998 by The American Society of Hematology.

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Self-collection of capillary blood using Tasso-SST devices for Anti-SARS-CoV-2 IgG antibody testing

PLoS ONE ◽

10.1371/journal.pone.0255841 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0255841

Author(s):

Tess Hendelman ◽

Anu Chaudhary ◽

Angela C. LeClair ◽

Kimberly van Leuven ◽

Jacqueline Chee ◽

...

Keyword(s):

Clinical Laboratory ◽

Venous Blood ◽

Epidemiologic Studies ◽

Capillary Blood ◽

Blood Collection ◽

Igg Antibodies ◽

Antibody Testing ◽

Igg Antibody ◽

Blood Samples ◽

Deming Regression

Background Efforts to minimize COVID-19 exposure during the current SARS-CoV-2 pandemic have led to limitations in access to medical care and testing. The Tasso-SST kit includes all of the components necessary for remote, capillary blood self-collection. In this study, we sought to investigate the accuracy and reliability of the Tasso-SST device as a self-collection device for measurement of SARS-CoV-2 IgG antibodies. Methods Capillary blood was obtained via unsupervised and supervised application of the Tasso-SST device, and venous blood was collected by standard venipuncture. Unsupervised self-collected blood samples underwent either extreme summer or winter-simulated shipping conditions prior to testing. Sera obtained by all three methods were tested concurrently using the EuroImmun anti-SARS-CoV-2 S1 IgG assay in a CLIA-certified clinical laboratory. Results Successful Tasso-SST capillary blood collection by unsupervised and supervised administration was completed by 93.4% and 94.5% of participants, respectively. Sera from 56 participants, 55 with documented (PCR+) COVID-19, and 33 healthy controls were then tested for anti-SARS-CoV-2 IgG antibodies. Compared to venous blood results, Tasso-SST-collected (unstressed) and the summer- and winter-stressed blood samples demonstrated Deming regression slopes of 1.00 (95% CI: 0.99–1.02), 1.00 (95% CI: 0.98–1.01), and 0.99 (95% CI: 0.97–1.01), respectively, with an overall accuracy of 98.9%. Conclusions Capillary blood self-collection using the Tasso-SST device had a high success rate. Moreover, excellent concordance was found for anti-SARS-CoV-2 IgG results between Tasso-SST capillary and standard venous blood-derived sera. The Tasso-SST device should enable widespread collection of capillary blood for testing without medical supervision, facilitating epidemiologic studies.

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An Assessment of Dried Blood-Spot Technology for Identifying Iron Deficiency

Blood ◽

10.1182/blood.v92.5.1807.417a03_1807_1813 ◽

1998 ◽

Vol 92 (5) ◽

pp. 1807-1813

Author(s):

James D. Cook ◽

Carol H. Flowers ◽

Barry S. Skikne

Keyword(s):

Iron Deficiency ◽

Transferrin Receptor ◽

Venous Blood ◽

Dried Blood Spots ◽

Epidemiologic Studies ◽

Capillary Blood ◽

Deficiency Anemia ◽

Blood Samples ◽

Blood Spots ◽

American Society

The present study was undertaken to assess the feasibility of using ferritin and transferrin receptor measurements on dried capillary blood spots to identify iron deficiency (ID) in public health surveys. Measurements on serum and blood spots prepared from venous blood were performed in 71 healthy subjects, 41 of whom were iron-replete and 30 who had ID, either without (n = 20) or with (n = 10) anemia. Parallel measurements were performed on hemolyzed whole blood and washed hemolyzed red blood cells to assess the erythrocyte contribution of ferritin and transferrin receptor to dried blood samples. The concentration of ferritin in dried blood samples was threefold higher than serum assays due to the release of ferritin from hemolyzed erythrocytes, which diminished the usefulness of ferritin measurements for detecting ID. On the other hand, there was negligible erythrocyte contribution to the measurement of transferrin receptor in dried blood spots. The most sensitive parameter in dried blood spots was the ratio of receptor/ferritin, which was suitable for identifying iron-deficiency anemia (IDA), but less reliable than serum assays for detecting milder ID without anemia. We conclude that tandem measurements of serum ferritin and transferrin receptor in dried blood spots can be used to facilitate the identification of IDA in epidemiologic studies. © 1998 by The American Society of Hematology.

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Comparison of capillary, venous and buffy coat blood samples in detecting Plasmodium species among malaria suspected patients attending at Hamusite health center. A cross-sectional study

BMC Infectious Diseases ◽

10.1186/s12879-021-06290-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Getu Abeje ◽

Woyneshet Gelaye ◽

Getaneh Alemu

Keyword(s):

Health Center ◽

Detection Rate ◽

Venous Blood ◽

Cross Sectional Study ◽

Buffy Coat ◽

Blood Film ◽

Capillary Blood ◽

Sectional Study ◽

Cross Sectional ◽

Blood Samples

Abstract Background Both capillary and venous blood samples have been interchangeably used for the diagnosis of malaria in Ethiopia. However, Plasmodium parasites are thought to be more concentrated in capillary than in venous blood. Hence, selecting a sample source where parasites are more concentrated is indispensable approach in order to maximize the accuracy of blood film microscopy. Therefore, the present study aimed to compare the detection rate and the parasitemia level of Plasmodium species from conventional capillary and venous blood films, and buffy coat preparations. Methods A facility based cross-sectional study was conducted from Feburary to March 2020 among 210 febrile patients attending Hamusite health center, northwest Ethiopia. Capillary and venous blood samples were collected and buffy coat was prepared from each sample. Thin and thick blood films were prepared, stained, and examined microscopically following standard protocol. Data were analysed using Statistical Package for Social Sciences Software version 20 and Med-Calc software version 19.3. Results Capillary blood buffy coat (61/210, 29.0%) had significantly higher detection rate as compared to capillary (48/210, 22.9%) and venous (42/210, 20.0%) blood films (p < 0.001). However, no significant difference was observed between capillary and venous blood films (p = 0.070) in detecting Plasmodium species. The highest and the lowest mean asexual stage parasite counts were found in capillary blood buffy coat (4692.88) and venous blood (631.43) films, respectively showing significant variations (p < 0.001). Mean gametocyte count was also highest in capillary blood buffy coat (3958.44). As compared to capillary blood buffy coat, the sensitivity of venous blood buffy coat, capillary blood film and venous blood film were 73.8, 78.7, 68.9%, respectively. Conclusion Capillary blood buffy coat samples showed the highest sensitivity in detecting and quantitating malaria parasites that its use should be promoted in clinical settings. However, conventional capillary and venous blood films could be used interchangeably.

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Effects of Different Methods Used to Take Blood Samples on Blood Glucose Measurements

Clinical Nursing Research ◽

10.1177/10547738211024782 ◽

2021 ◽

pp. 105477382110247

Author(s):

Eda Ergin ◽

Ayten Zaybak

Keyword(s):

Blood Glucose ◽

Glucose Tolerance Test ◽

Venous Blood ◽

Tolerance Test ◽

Capillary Blood ◽

Oral Glucose ◽

Blood Samples ◽

Significant Difference ◽

Measurement Results ◽

Quasi Experimental

The purpose of this study is to compare whether or not there is a difference between venous and capillary blood samples in blood glucose measurements and investigate the effects of different aseptic methods used in skin cleaning before collecting blood samples on measurement results. This quasi-experimental study was conducted with 109 patients. The capillary first and second blood drop values taken from the patients after fasting and at 2 hours following 75 g oral glucose tolerance test (OGTT) and capillary and venous blood glucose values were compared. There was no significant difference between the median venous blood glucose value and the capillary second blood drop value taken after wiping the finger with alcohol. There was no significant difference between the first and second blood drop values of capillary blood glucose 2 hours after OGTT.

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Blood Glucose Assay Using Dextrostix and a Reflectance Meter

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456327200900144 ◽

1972 ◽

Vol 9 (1-6) ◽

pp. 91-94 ◽

Cited By ~ 6

Author(s):

I. W. Percy-Robb ◽

R. S. McMaster ◽

A. D. B. Harrower ◽

L. J. P. Duncan

Keyword(s):

Blood Glucose ◽

Venous Blood ◽

Reference Method ◽

Capillary Blood ◽

Blood Samples ◽

Laboratory Staff ◽

Glucose Assay ◽

Reflectance Meter ◽

High Degree ◽

Blood Glucose Concentrations

The ‘Dextrostix’-reflectance meter system for blood glucose analysis has been evaluated using a blood glucose reference method. A high degree of concordance between the two methods was obtained when analyses were performed by skilled laboratory staff on venous blood samples containing fluoride, with a 75 s contact time. Skilled laboratory staff performed significantly better than unskilled staff. Capillary blood glucose concentrations correlated poorly with concentrations in venous blood samples taken at the same time as the capillary blood.

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