Performance evaluation of the point-of-care SAMBA I and II HIV-1 Qual whole blood tests

Remote areas of many low and middle income (LMI) countries have poor access to HIV viral load (HIV VL) testing. The SAMBA-II (Simple Amplification-based Assay) Semi-Q Whole Blood Test (Diagnostics for the Real World (DRW), Cambridge, UK) is a point of care assay which uses leucodepletion technology to allow whole blood testing in remote settings. 1540 consecutive HIV-positive clinic patients in Cameroon (250), UK (633), Ukraine (412) and Zimbabwe (245) donated venous blood (all countries) and finger-prick blood (all except UK) for testing on SAMBA-II. SAMBA II results were compared with simultaneous plasma results on the Abbott RealTime HIV-1 (Abbott Molecular, Des Plaines, IL) viral load assay and interpreted as either <1000 RNA copies/ml or ≥1000 RNA copies/ml. For 1528 venous whole-blood samples tested on SAMBA II, overall percent agreement with the reference test at a cut-off of HIV VL ≥1000 cps/ml was 96.9% (1480/1528 95% CI 95.9-97.7), negative percent agreement 97.7% (1259/1289 95% CI 96.7-98.4), positive percent agreement 92.5% (221/239 95% CI 88.4-95.5). For 854 finger-prick samples there was 95.0% (811/854 95% CI 93.3-96.3) overall percent agreement; negative percent agreement 98.0% (625/638, 95% CI 96.5-98.9); positive percent agreement 86.1% (186/216 95% CI 80.8-90.4). These rose to 93.5% (82.1, 98.6), 97.6% (95.6, 98.8) and 95.6% (93.3, 97.3) after exclusion of aberrant results from the Ukraine centre. These results show a high level of agreement between SAMBA-II and a laboratory-based assay. SAMBA-II has a performance that is suitable to use as a VL point of care assay in remote settings

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Comparison of Rapid Point-of-Care Tests for Detection of Antibodies to Hepatitis C Virus

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv101 ◽

2015 ◽

Vol 2 (3) ◽

Cited By ~ 17

Author(s):

Dennis G. Fisher ◽

Kristen L. Hess ◽

Erlyana Erlyana ◽

Grace L. Reynolds ◽

Catherine A. Cummins ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Hepatitis B ◽

Whole Blood ◽

Point Of Care ◽

Antibody Test ◽

The United States ◽

Blood Tests ◽

Hcv Antibody ◽

Point Of Care Tests

Abstract Background. Hepatitis C is one of the most prevalent blood-borne diseases in the United States. Despite the benefits of early screening, among 3.2 million Americans who are infected with hepatitis C virus (HCV), 50%–70% are unaware of their infection status. Methods. Data were collected between 2011 and 2014, from 1048 clients who were in the following groups: (1) injection drug users, (2) women at sexual risk, (3) gay and bisexual men, and (4) transgender individuals. The sensitivity and specificity of point-of-care tests included (1) the MedMira rapid human immunodeficiency virus (HIV)/HCV antibody test, (2) MedMira hepatitis B (HBV)/HIV/HCV antibody test, (3) Chembio HCV Screen Assay used with both whole blood and (4) oral specimens, (5) Chembio HIV-HCV Assay also used with both whole blood and (6) oral specimens, (7) Chembio HIV-HCV-Syphilis Assay, and (8) OraSure HCV Rapid Antibody Test used with whole blood. The gold standard for the HCV tests were HCV enzyme immunoassay (EIA) 2.0. Results. OraSure had the highest sensitivity at 92.7% (95% confidence interval [CI] = 88.8%–96.5%) followed closely by Chembio's 3 blood tests at 92.1% (95% CI = 87.7%–96.4%), 91.5% (95% CI = 87.2%–95.7%), and 92.3% (95% CI = 88.4%–96.2%). The sensitivities of MedMira HIV/HCV and MedMira HIV/HCV/HBV tests were the lowest, at 79.1% (95% CI = 72.6%–85.5%), and 81.5% (95% CI = 75.2%–87.8%), respectively. Specificity for the OraSure was 99.8% (95% CI = 99.4%–100%); specificity for the Chembio blood tests was 99.2% (95% CI = 98.6%–99.9%), 99.4% (95% CI = 98.8%–99.9%), and 99.3% (95% CI = 98.8%–99.9%); and specificity for the MedMira was100% and 100%. False-negative results were associated with HIV and hepatitis B core antibody serostatus. Conclusions. The OraSure and Chembio blood tests (including those multiplexed with HIV and syphilis) appear to good performance characteristics. This study has identified potential limitations of rapid testing in those testing positive for HIV and HBcAb. There should be discussion of updates to the 2013 CDC guidance.

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WITHDRAWN: Rapid, point-of-care extraction of HIV-1 proviral DNA from whole blood for detection by real-time PCR

Journal of Clinical Microbiology ◽

10.1128/jcm.00092-09 ◽

2009 ◽

Author(s):

S. R. Jangam ◽

D. H. Yamada ◽

S. M. McFall ◽

D. M. Kelso

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Whole Blood ◽

Point Of Care ◽

Proviral Dna ◽

Hiv 1

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Performance evaluation of the point-of-care INSTI™ HIV-1/2 antibody test in early and established HIV infections

Journal of Clinical Virology ◽

10.1016/j.jcv.2017.03.012 ◽

2017 ◽

Vol 91 ◽

pp. 90-94 ◽

Cited By ~ 13

Author(s):

Sarah Adams ◽

Wei Luo ◽

Laura Wesolowski ◽

Stephanie E. Cohen ◽

Philip J. Peters ◽

...

Keyword(s):

Performance Evaluation ◽

Point Of Care ◽

Antibody Test ◽

Hiv Infections ◽

Hiv 1

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Brazilian Program For HIV Point-Of-Care Test Evaluation: A Decade’s Experience

International Archives of Medicine ◽

10.3823/2532 ◽

2017 ◽

Vol 10 ◽

Author(s):

Orlando Da Costa Ferreira Jr. ◽

Nazle Mendonca Collaco Veras ◽

Ana Flávia Nassif Coelho Pires ◽

Maria Luiza Bazzo ◽

Leonardo Rapone Da Motta ◽

...

Keyword(s):

Western Blot ◽

Whole Blood ◽

Oral Fluid ◽

Point Of Care ◽

Hiv Positive ◽

Hiv Diagnosis ◽

Evaluation Program ◽

Test Batch ◽

Hiv 1 ◽

Selection Of

The point-of-care tests (POCTs) for HIV diagnosis have been widely used in Brazil in order to expand and to allow HIV diagnosis outside health units including remote areas, such as the Amazon region. In order to guarantee the quality of HIV diagnostics based on rapid tests, the Brazilian Ministry of Health (MoH) implemented the HIV POCT Evaluation Program. This study compiles the Brazilian experience acquired over the last 13 years conducting the HIV POCT Evaluation Program. Methods and Findings The selection of tests was based on the interest of manufacturers to qualify for the MoH tenders. Each round was performed with fresh whole blood and oral fluid samples, always including HIV positive and negative ones. In addition to the POCT, every sample was submitted to a reference testing protocol, based on an immunoassay followed by Western blot. The POCTs were evaluated for clinical sensitivity, clinical specificity, assay operational characteristics, detection of HIV-2 antibodies, sensitivity to subtypes panels; and sensitivity to seroconversion panels. Since its implementation in 2003, the POCT evaluation protocol has undergone some modifications aiming to improve and simplify the evaluation process, to know: (i) for HIV-positive samples, perform EIA and Western blot only if the POCT is non-reactive; (ii) reduction from 800 to 600 HIV negative samples; (iii) increase from one to three subtype panels (including HIV-2 samples); and (iv) inclusion of seroconversion panel. We evaluated six tests, four of which met the sensitivity criteria of 99.5%: BD Chek™ HIV Multi-test (whole blood), HIV 1/2 Colloidal Gold (whole blood), OraQuick ADVANCE® Rapid HIV-1/2 Antibody Test (whole blood and oral fluid) and TR DPP HIV-1/2 (whole blood, plasma and oral fluid). Regarding other evaluated criteria, all assays met the requirements. Conclusions The successful Brazilian policy on POCT use for HIV infection diagnosis includes the evaluation of the POCT itself in addition to appropriate selection of tests to be acquired and nationwide distributed to the public health facilities, control of each test batch distributed by the MoH, proper and easily accessible training to all health professionals involved in rapid testing through distance learning tools, and continued evaluation of POCT use through external quality assessment.

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Laboratory Evaluation of the Liat HIV Quant (IQuum) Whole-Blood and Plasma HIV-1 Viral Load Assays for Point-of-Care Testing in South Africa

Journal of Clinical Microbiology ◽

10.1128/jcm.03325-14 ◽

2015 ◽

Vol 53 (5) ◽

pp. 1616-1621 ◽

Cited By ~ 30

Author(s):

Lesley Scott ◽

Natasha Gous ◽

Sergio Carmona ◽

Wendy Stevens

Keyword(s):

South Africa ◽

Viral Load ◽

Whole Blood ◽

Point Of Care ◽

Laboratory Evaluation ◽

Point Of Care Testing ◽

Hiv 1

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Leukodepletion as a Point-of-Care Method for Monitoring HIV-1 Viral Load in Whole Blood

Journal of Clinical Microbiology ◽

10.1128/jcm.02853-14 ◽

2014 ◽

Vol 53 (4) ◽

pp. 1080-1086 ◽

Cited By ~ 10

Author(s):

Logan Titchmarsh ◽

Clement Zeh ◽

Thierry Verpoort ◽

Jean-Pierre Allain ◽

Helen Lee

Keyword(s):

Viral Load ◽

Whole Blood ◽

Clinical Performance ◽

Point Of Care ◽

White Blood Cells ◽

Cell Content ◽

Loss To Follow Up ◽

Resource Limited ◽

Virus Retention ◽

Hiv 1

In order to limit the interference of HIV-1 cellular nucleic acids in estimating viral load (VL), the feasibility of leukodepletion of a small whole-blood (WB) volume to eliminate only leukocyte cell content was investigated, using a selection of filters. The efficacy of leukocyte filtration was evaluated by counting, CD45 quantitative PCR, and HIV-1 DNA quantification. Plasma HIV-1 was tested by real-time reverse transcription (RT)-PCR. A specific, miniaturized filter was developed and tested for leukocyte and plasma virus retention, WB sample dilution, and filtration parameters in HIV-1-spiked WB samples. This device proved effective to retain >99.9% of white blood cells in 100 μl of WB without affecting plasma VL. The Samba sample preparation chemistry was adapted to use a leukodepleted WB sample for VL monitoring using the point-of-care Samba-1 semiautomated system. The clinical performance of the assay was evaluated by testing 207 consecutive venous EDTA WB samples from HIV-1-infected patients attending a CD4 testing clinic. Most patients were on antiretroviral treatment (ART), but their VL status was unknown. Compared to the Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test, the new Samba assay had a concordance of 96.5%. The use of the Samba system with a VL test for WB might contribute to HIV-1 ART management and reduce loss-to-follow-up rates in resource-limited settings.

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