Quality assuring HIV point of care testing using whole blood samples

Abstract Background: The purpose of this study was to validate the use of whole-blood samples in the determination of circulating forms of prostate-specific antigen (PSA). Methods: Blood samples of hospitalized prostate cancer and benign prostatic hyperplasia patients were collected and processed to generate whole-blood and serum samples. Three different rapid two-site immunoassays were developed to measure the concentrations of total PSA (PSA-T), free PSA (PSA-F), and PSA-α1-antichymotrypsin complex (PSA-ACT) to detect in vitro changes in whole-blood samples immediately after venipuncture. The possible influence of muscle movement on the release of PSA from prostate gland was studied in healthy men by measuring the rapid in vitro whole-blood kinetics of PSA forms before and after 15 min of physical exercise on a stationary bicycle. Results: Rapid PSA-T, PSA-F, and PSA-ACT assays were designed using a 10-min sample incubation. No significant changes were detected in the concentrations of PSA-T, PSA-F, and PSA-ACT from the earliest time point of 12–16 min compared with measurements performed up to 4 h after venipuncture. Physical exercise did not influence the concentrations of the circulating forms of PSA. Hematocrit-corrected whole-blood values of PSA-T and PSA-F forms were comparable to the respective serum values. Calculation of the percentage of PSA-F (PSA F/T ratio × 100) was similar irrespective of the sample format used, i.e., whole blood or serum. Conclusions: We found that immunodetectable PSA forms are likely at steady state immediately after venipuncture, thus enabling the use of anticoagulated whole-blood samples in near-patient settings for point-of-care testing, whereas determinations of PSA (e.g., PSA-T, PSA-F, or PSA-ACT) performed within the time frame of the office visit would provide results equivalent to conventional analyses performed in serum.

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European Concerted Action on Anticoagulation (ECAA): International Normalized Ratio Variability of CoaguChek and TAS Point-of-Care Testing Whole Blood Prothrombin Time Monitors

Thrombosis and Haemostasis ◽

10.1055/s-0037-1613345 ◽

2002 ◽

Vol 88 (12) ◽

pp. 992-995 ◽

Cited By ~ 3

Author(s):

M. Keown ◽

N. Chauhan ◽

C. Shiach ◽

A. M. H. P. van den Besselaar ◽

A. Tripodi ◽

...

Keyword(s):

Prothrombin Time ◽

Whole Blood ◽

Point Of Care ◽

International Normalized Ratio ◽

Operator Technique ◽

Concerted Action ◽

Point Of Care Testing ◽

Blood Samples ◽

International Normalised Ratio ◽

Whole Blood Samples

SummaryThe object was to assess the variability in displayed International Normalised Ratio (INR) between monitors of the same manufacture using whole blood samples from the same subjects. Two brands of monitor, CoaguChek Mini and the TAS PT-NC were tested.14 instruments of each brand were tested on the same day at the same laboratory by the same operator using identical blood samples to avoid between-centre differences in samples and operator technique. Whole blood samples from two normal donors and four coumarintreated patients were tested to assess between-instrument variability of INR.Results have been coded. There was a much wider dispersion of INR on Brand B than on Brand A. One Brand A instrument failed to give a result with one of the two whole blood samples from one patient. One Brand B monitor gave an aberrant result with one of the samples from a normal subject.On both brands of monitor, INR variability appeared to be due mainly to duplication differences rather than between-instrument variability on both normal and coumarin whole blood samples.

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A Quantitative Immunochromatography Assay of Whole Blood Samples for Antigen-specific IgE—A New Method for Point of Care Testing for Allergens—

Allergology International ◽

10.2332/allergolint.54.393 ◽

2005 ◽

Vol 54 (3) ◽

pp. 393-399 ◽

Cited By ~ 4

Author(s):

Tetsuya Ono ◽

Kazuyuki Sugiyama ◽

Takashi Kuroda ◽

Masahide Kawamura ◽

Shinsuke Arao ◽

...

Keyword(s):

Whole Blood ◽

Point Of Care ◽

Specific Ige ◽

New Method ◽

Point Of Care Testing ◽

Blood Samples ◽

Whole Blood Samples

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The Variability of Results Between Point-of-Care Testing Glucose Meters and the Central Laboratory Analyzer

Archives of Pathology & Laboratory Medicine ◽

10.5858/2006-130-1527-tvorbp ◽

2006 ◽

Vol 130 (10) ◽

pp. 1527-1532

Author(s):

Adil I. Khan ◽

Yolanda Vasquez ◽

Jacquelyn Gray ◽

Frank H. Wians Jr ◽

Martin H. Kroll

Keyword(s):

Whole Blood ◽

Point Of Care ◽

Clinical Results ◽

Central Laboratory ◽

Point Of Care Testing ◽

Blood Samples ◽

Glucose Meter ◽

Whole Blood Samples ◽

Blood Specimens ◽

Laboratory Analyzer

Abstract Context.—Point-of-care testing glucose meters are strongly recommended in the management of diabetes and are increasingly being used for making therapeutically important decisions. Thus, it is essential that their results correlate well with those of laboratory analyzers. Objectives.—To test the reliability of point-of-care testing glucose meters. Design.—Two studies were performed: (1), an in-house study comparing accuracy of point-of-care testing glucose meters with a reference analyzer using fresh whole blood specimens (2), a real-time comparison of (a) 2 successive glucose meter readings and (b) glucose meter reading to central laboratory analyzer reading. Setting.—(1), Seven glucose meters from 4 manufacturers were compared with the Yellow Springs YSI 2300 blood glucose analyzer using whole blood without preservative. (2), (a) Whole blood samples were read within 5 minutes of each other using Accu-Chek meters and (b) between a glucose meter and a Hitachi laboratory analyzer. Results.—(1) Within the Accu-Chek group of glucose meters, fresh, preservative-free whole blood samples showed the lowest bias. (2) At the hypoglycemic level, successive glucose meter readings agreed well, but there was considerable disagreement between glucose meter and central laboratory values. Because laboratory analyzers are of proven accuracy, they are used as the reference. In the glucose meter–central laboratory analyzer correlation, for both hypoglycemic and hyperglycemic values, readings in which the differences were greater than 10% occurred more than 61% of the time. In the hypoglycemic range, differences greater than 20% occurred 57% of the time. Conclusions.—One should scrutinize point-of-care testing glucose meter readings at the hypoglycemic and hyperglycemic levels and whenever possible to corroborate these clinical results with central laboratory analyzers.

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Development of a new point-of-care testing system for measuring white blood cell and C-reactive protein levels in whole blood samples

Clinica Chimica Acta ◽

10.1016/j.cca.2014.03.004 ◽

2014 ◽

Vol 433 ◽

pp. 145-149 ◽

Cited By ~ 10

Author(s):

Kazuhiko Kotani ◽

Takaomi Minami ◽

Toshiaki Abe ◽

Junji Sato ◽

Nobuyuki Taniguchi ◽

...

Keyword(s):

Blood Cell ◽

Whole Blood ◽

Point Of Care ◽

Testing System ◽

Point Of Care Testing ◽

C Reactive Protein ◽

Blood Samples ◽

Protein Levels ◽

Reactive Protein ◽

Whole Blood Samples

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Performance of immunofluorometric point-of-care assays for free pregnancy-associated plasma protein A detection in whole blood samples

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2008.002 ◽

2008 ◽

Vol 46 (1) ◽

Cited By ~ 3

Author(s):

Saara Wittfooth ◽

Qiu-Ping Qin ◽

Kim Pettersson

Keyword(s):

Plasma Protein ◽

Whole Blood ◽

Point Of Care ◽

Protein A ◽

Blood Samples ◽

Whole Blood Samples

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Longitudinal Evaluation of mRNA Vaccinated Subjects using a Quidel Multianalyte Point-of-Care SARS-CoV-2 IgG Immunoassay

10.1101/2021.05.06.21256544 ◽

2021 ◽

Author(s):

Xi Chen ◽

Sarika Agarwal ◽

Stewart Hoelscher ◽

Richard Egan ◽

Dipesh Jaiswal ◽

...

Keyword(s):

Immune Response ◽

Whole Blood ◽

Point Of Care ◽

World Population ◽

Igg Antibody ◽

Blood Samples ◽

Whole Blood Samples ◽

Immuno Assay ◽

Diseased State ◽

Prior Infection

Infection from SARS-CoV-2 elicits an immune response to the nucleocapsid (N) and spike proteins (subunits S1 and S2). In this study, we set out to understand the utility of the multiplexed Quidel Sofia 2 SARS-CoV-2 IgG Antibody Fluorescent Immuno-Assay (FIA) that measures IgG antibodies against these three primary SARS-CoV-2 antigens from a single sample in 15 minutes. Using this assay with samples that were collected prior to the COVID-19 pandemic (n=816) and diseased state samples (n=99), the specificities for the three antigens were 98.4-99.9% and 98.0-100.0%, respectively. A longitudinal study was designed to collect weekly fingerstick, venous whole blood, serum and plasma samples from subjects vaccinated with the Moderna or Pfizer/BioNtech mRNA vaccines. The majority of these enrolled subjects had no known prior infection while a subset was known to have had prior COVID-19 infection. We found that the fingerstick whole blood samples performed as effectively as serum, plasma, and venous whole blood samples with a 95.8-99.5% agreement allowing physicians in a near-patient setting to rapidly provide results to their patients. Additionally, as this assay measures an IgG response against three viral proteins, S1, S2 and N, we were able to characterize immune response between i) naturally infected subjects, ii) vaccinated subjects with no prior infection, iii) vaccinated subjects with known prior infection, and iv) vaccinated subjects with prior asymptomatic exposure/infection. The Quidel Sofia 2 SARS-CoV-2 IgG FIA will aid in providing insights to the protective humoral responses as an increasing number of the world population is vaccinated against SARS-CoV-2.

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