Potential for false-positive HIV test results using rapid HIV testing algorithms

Background: In order to scale up access to HIV counselling and testing in Nigeria, an HIV diagnostic algorithm based on rapid testing was adopted. However, there was the need to further evaluate the testing strategy in order to better assess its performance, because of the potential for false positivity.Objectives: The objective of this study was to compare positive HIV test results obtained from the approved rapid testing algorithm with results from western blot tests performed on samples from the same patient.Methodology: A retrospective review was conducted of HIV screening and confirmatory results for patients seen between 2007 and 2008. Rapid test and western blot results were extracted and compared for concordance. Discordant results were further reviewed using a combination of HIV-1 RNA viral load and CD4+ cell count test results and clinical presentation from medical records.Results: Analysis of 2228 western blot results showed that 98.3% (n = 2191) were positive for HIV-1, 0.4% (n = 8) were positive for HIV-2 and 0.3% (n = 7) were dual infections (positive for both HIV-1 and HIV-2); 0.6% (n = 13) were indeterminate and 0.4% (n = 9) were negative. Further investigation of the 13 indeterminate results showed nine to be HIV-1 positive and four to be HIV-negative, for a total of 13 negative results. The positive predictive value of the HIV counselling and testing algorithm was 99.4%.Conclusion: Using the rapid testing algorithm alone, false positives were detected. Therefore, effective measures such as training and retraining of staff should be prioritised in order to minimise false-positive diagnoses and the associated potential for long-term psychological and financial impact on the patients.

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Evaluation of antenatal rapid human immunodeficiency virus testing in rural South Africa

Southern African Journal of HIV Medicine ◽

10.4102/sajhivmed.v19i1.771 ◽

2018 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Tivani P. Mashamba-Thompson ◽

Pravi Moodley ◽

Benn Sartorius ◽

Paul K. Drain

Keyword(s):

Pregnant Women ◽

Hiv Testing ◽

Rapid Test ◽

Test Results ◽

Rapid Testing ◽

Hiv Test ◽

Hiv Rapid Testing ◽

Immunodeficiency Virus ◽

Rapid Tests ◽

Testing Algorithm

Introduction: South African guidelines recommend two rapid tests for diagnosing human immunodeficiency virus (HIV) using the serial HIV testing algorithm, but the accuracy and compliance to this algorithm is unknown in rural clinics. We evaluated the accuracy of HIV rapid testing and the time to receiving test results among pregnant women in rural KwaZulu-Natal (KZN).Method: We observed the accuracy of rapid HIV testing algorithms for 208 consenting antenatal patients accessing voluntary HIV testing services in nine rural primary healthcare (PHC) clinics in KZN. A PHC-based HIV counsellor obtained finger-prick whole blood from each participant to perform rapid testing using the Advanced Quality™ One Step anti-HIV (1&2) and/or ABON™ HIV 1/2/O Tri-Line HIV test. A research nurse obtained venous blood for an enzyme-linked immunosorbent assay (ELISA) HIV test, which is the gold standard diagnostic test. We recorded the time of receipt of HIV test results for each test.Results: Among 208 pregnant women with a mean age of 26 years, 72 women from nine rural PHC clinics were identified as HIV-positive by two rapid tests with an HIV-prevalence of 35% (95% Bayesian credibility intervals [BCI]: 28% – 41%). Of the 208 patients, 135 patients from six clinics were tested with the serial HIV testing algorithm. The estimated sensitivity and specificity for the 135 participants were 100% (95% confidence interval [CI]: 93% – 100%) and 99% (CI: 95% – 100%), respectively. The positive predictive value and negative predictive value were estimated at 98% (CI: 94% – 100%) and 95% (CI: 88% – 99%), respectively. All women received their HIV rapid test results within 20 min of testing. Test stock-out resulted in poor test availability at point-of-care, preventing performance of a second HIV test in three out of nine PHC clinics in rural KZN.Conclusion: Despite the poor compliance with national guidelines for HIV rapid testing services, HIV rapid test results provided to pregnant women in rural PHC clinics in KZN were generally accurate and timely. Test stock-out was shown to be one of the barriers to test availability in rural PHC clinics, resulting in poor compliance with guidelines. We recommend a compulsory confirmation HIV rapid test for all HIV-negative test results obtained from pregnant patients in rural and resource-limited settings.

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Potential for false positive HIV test results with the serial rapid HIV testing algorithm

BMC Research Notes ◽

10.1186/1756-0500-5-154 ◽

2012 ◽

Vol 5 (1) ◽

Cited By ~ 25

Author(s):

Steven Baveewo ◽

Moses R Kamya ◽

Harriet Mayanja-Kizza ◽

Robin Fatch ◽

David R Bangsberg ◽

...

Keyword(s):

Hiv Testing ◽

False Positive ◽

Test Results ◽

Rapid Hiv Testing ◽

Hiv Test ◽

Testing Algorithm

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Routine HIV Test Results in 6 US Clinical Laboratories Using the Recommended Laboratory HIV Testing Algorithm With Geenius HIV 1/2 Supplemental Assay

Sexually Transmitted Diseases ◽

10.1097/olq.0000000000001102 ◽

2020 ◽

Vol 47 ◽

pp. S13-S17 ◽

Cited By ~ 1

Author(s):

Laura G. Wesolowski ◽

Pollyanna R. Chavez ◽

Ana María Cárdenas ◽

Alex Katayev ◽

Patricia Slev ◽

...

Keyword(s):

Hiv Testing ◽

Test Results ◽

Clinical Laboratories ◽

Hiv Test ◽

Testing Algorithm ◽

Hiv 1

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Absence of routine molecular testing and prevalence of HIV-2 infection in regions hardest-hit by HIV infection

The Journal of Infection in Developing Countries ◽

10.3855/jidc.2298 ◽

2012 ◽

Vol 6 (12) ◽

pp. 854-859 ◽

Cited By ~ 3

Author(s):

Joseph C Forbi ◽

Mathew D Esona ◽

Hellen O Iperepolu ◽

Moses P Adoga ◽

Simon M Agwale

Keyword(s):

Hiv Infection ◽

Sex Workers ◽

False Negative ◽

Rapid Test ◽

Molecular Testing ◽

Test Results ◽

Active Population ◽

Hiv Test ◽

In Series ◽

Hiv 1

Introduction: Investigating the incidence and dynamics of HIV-2 and false-negative HIV test results in a highly sexually active population where frequent opportunities exist for acquiring and transmitting infections provides additional understanding of the epidemiology of the virus in Africa. Methodology: The HIV status of 900 active female sex workers (FSWs) was determined using two lateral flow rapid assays in series. The second rapid test device incorporates type-specific recombinant peptides that discriminate between HIV-1 and HIV-2 infection. HIV sero-negative samples were re-tested for HIV infection and their viral loads determined using the NucliSENS real-time nucleic acid sequence-based amplification (NASBA) platform. Results: In total, 335 FSWs were determined to be HIV positive, the majority (227; 67.8%) of whom were between the ages of 20 and 30 years. Eighteen (5.4%) were found to have evidence of HIV-2 infection, 17 of whom were co-infected with HIV-1. Only one HIV-2 mono-infection was observed. Out of 565 HIV-negative individuals determined by serology, 11(1.9%; p>0.05) were found to be HIV-1 positive when tested via the NASBA platform. Conclusion: False negative test results, HIV-2 infection, and complex transmission networks among FSWs may aid in fueling the HIV epidemic in the Nigerian population. These findings demonstrate the need to reevaluate the quality of HIV serological diagnostics, control services, and stress the need for widespread introduction of molecular testing among high-risk populations in the country.

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Low Rate of False-Positive Results with Use of A Rapid HIV Test

Infection Control and Hospital Epidemiology ◽

10.1086/502061 ◽

2002 ◽

Vol 23 (6) ◽

pp. 335-337 ◽

Cited By ~ 10

Author(s):

Cassandra D. Salgado ◽

Heidi L. Flanagan ◽

Doris M. Haverstick ◽

Barry M. Farr

Keyword(s):

Enzyme Immunoassay ◽

False Positive ◽

Diagnostic System ◽

Rapid Test ◽

Occupational Exposures ◽

High Rate ◽

Negative Results ◽

Hiv Test ◽

Rapid Hiv Test ◽

Positive Results

Background:Occupational exposure to human immunodeficiency virus (HIV) is an important threat to healthcare workers. Centers for Disease Control and Prevention guidelines recommend prompt institution of prophylaxis. This requires (1) immediate prophylaxis after exposure, pending test results that may take more than 24 hours in many hospitals; or (2) performance of a rapid test. The Single Use Diagnostic System (SUDS)® HIV-1 Test is used to screen rapidly for antibodies to HIV type 1 in plasma or serum, with a reported sensitivity of more than 99.9%. We used this test from January 1999 until September 2000, when it was withdrawn from the market following reports claiming a high rate of false-positive results.Methods:We reviewed the results of postexposure HIV testing during 21 months.Results:A total of 884 SUDS tests were performed on source patients after occupational exposures (883 negative results, 1 reactive result). The results of repeat SUDS testing on the reactive specimen were also reactive, but the results of enzyme immunoassay and Western blot testing were negative. A new specimen from the same patient showed a negative result on SUDS testing. This suggested a specificity of 99.9%. In the 4 months after SUDS testing was suspended, there was 1 false-positive result on enzyme immunoassay for 1 of 132 source patients (presumed specificity, 99.2%).Conclusion:Use of the SUDS test facilitated rapid and accurate evaluation of source specimens, obviating unnecessary prophylaxis.

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Barriers and facilitators associated with HIV testing uptake in South African health facilities offering HIV Counselling and Testing

Health SA Gesondheid ◽

10.4102/hsag.v21i0.938 ◽

2016 ◽

Vol 21 ◽

pp. 86-95 ◽

Cited By ~ 6

Author(s):

Neo Mohlabane ◽

Bomkazi Tutshana ◽

Karl Peltzer ◽

Aziza Mwisongo

Keyword(s):

Hiv Testing ◽

South African ◽

Health Workers ◽

Scale Up ◽

Health Facilities ◽

Barriers And Facilitators ◽

Hiv Care ◽

Treatment Needs ◽

Hiv Test ◽

Hiv Counselling And Testing

Background: The scale-up of HIV Counselling and Testing (HCT) in South Africa to 4500 public health facilities and the service's provision in mobile and non-medical sites was aimed at increasing HCT uptake. However, some people still have never had an HIV test.Objective: An HCT survey was carried out to ascertain barriers and facilitators for HIV testing in South Africa.Methods: A cross-sectional survey of 67 HCT-offering health facilities in 8 South African provinces was undertaken. Individuals (n = 489) who had not tested for HIV on the day of the site visit were interviewed on awareness of HCT services, HIV testing history and barriers to HIV testing. Frequencies were run to describe the sample characteristics, barriers and facilitators to HIV testing. Bivariate and multivariate logistic regression was usedt o identify the association between never tested for HIV with socio-demographics, awareness of HCT services and type of HCT facilities.Results: In all 18.1% participants never had an HIV test. Major barriers to HCT uptake comprise being scared of finding out one's HIV test result or what people may say, shyness or embarrassment, avoidance of divulging personal information to health workers and fear of death. In multivariate analysis the age group 55 years and older, and not being recommended to have an HIV test were associated with never had an HIV test. Potential facilitators for HIV testing include community or household HIV testing, providing incentives for those who test for HIV, mandatory HIV testing and disclosure of HIV status by those who test HIV positive.Conclusion: The benefits of HCT which include the reduction of HIV transmission, the availability of HIV care and treatment needs to be emphasized to enhance HCT uptake.

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INCIDENCE OF HIV-1 AND HIV-2 ANTIBODIES IN HEMOPHILIACS

10.1055/s-0038-1644142 ◽

1987 ◽

Author(s):

W Schramm ◽

L G Gürtler ◽

H Pohlmann ◽

I Weigel ◽

J Eberie ◽

...

Keyword(s):

The Other ◽

Clotting Factor ◽

Test Results ◽

Clotting Factors ◽

Negative Results ◽

Group 12 ◽

Hiv Test ◽

In The Beginning ◽

Anti Hiv ◽

Hiv 1

The presence of antibodies to HIV-1 (anti-HIV-1) was tested in 167 hemophiliacs surveyed and treated at Munich hemophilia center. Increasing numbers of HIV infected patients were observed in the years 1981 to 1986 from 0% to 51,5% (86 positive patients in January 1987 of 167 followed patients). Most of the seroconver-sions occured between 1982 and 1984. The 150 clinically severe affected hemophiliacs (F-VIII-levels up to 5% and need of replacement therapy) showed positive HIV-test results in 55,3% (83 patients) and negative results in 44,7% (67 patients). 5 patients died since 1981, one because of AIDS. 17 patients were not seen since 1984, 14 of those belong to the severly affected group, 12 of them were negative. Since spring 1985 only heat or chemically treated clotting factor preparations are used for substitution. Despite this still 5 seroconversions were observed. Two may be attributed to the use of a preparation heat inactivated in dry state, this preparation is no longer used. The other 3 seroconversions possibly were caused by an occasional use of an noninactivated preparation in the beginning of the change to inactivated clotting factor preparations. 38 of the anti-HIV-1 positive sera were tested for the presence of HIV-2 antibodies also. The methods were ELISA,immunofluorescence and immunoblot. HIV-2 (LAV-2) for these tests was kindly provided by L. Montagnier. Antibodies specific for HIV-2 antigens were not detected, but crossreactions were observed between anti-HIV-1 with HIV-2 antigens particularly epitopes on HIV-2-p27.The data indicate that the use of adequately inactivated clotting factors can prevent infection of hemophilia patients by this route and that HIV-2 was not present in the clotting factor preparations used for the substitution of this group of patients. The incidence of full blown AIDS since 1981 in our group of hemophiliacs is still low (1,2%).

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Evaluation of Rapid Testing Algorithms for Venue-based Anonymous HIV Testing among Non-HIV-Positive Men Who Have Sex with Men, National HIV Behavioral Surveillance (NHBS), 2017

Journal of Community Health ◽

10.1007/s10900-020-00871-3 ◽

2020 ◽

Vol 45 (6) ◽

pp. 1228-1235

Author(s):

Shamaya Whitby ◽

◽

Amanda Smith ◽

Rebecca Rossetti ◽

Johanna Chapin-Bardales ◽

...

Keyword(s):

Hiv Testing ◽

Confirmatory Test ◽

Test Results ◽

Rapid Testing ◽

Behavioral Surveillance ◽

National Hiv Behavioral Surveillance ◽

Hiv Test ◽

Hiv Rapid Testing ◽

Testing Algorithms ◽

Sex With Men

Abstract HIV rapid testing algorithms (RTAs) using any two orthogonal rapid tests (RTs) allow for on-site confirmation of infection. RTs vary in performance characteristics therefore the selection of RTs in an algorithm may affect identification of infection, particularly if acute. National HIV Behavioral Surveillance (NHBS) assessed RTAs among men who have sex with men recruited using anonymous venue-based sampling. Different algorithms were evaluated among participants who self-reported never having received a positive HIV test result prior to the interview. NHBS project areas performed sequential or parallel RTs using whole blood. Participants with at least one reactive RT were offered anonymous linkage to care and provided a dried blood spot (DBS) for testing at CDC. Discordant results (RT-1 reactive/RT-2 non-reactive) were tested at CDC with lab protocols modified for DBS. DBS were also tested for HIV-1 RNA (VL) and antiretroviral (ARV) drug levels. Of 6500 RTAs, 238 were RT-1 reactive; of those, 97.1% (231/238) had concordant results (RT-1/RT-2 reactive) and 2.9% (7/238) had discordant results. Five DBS associated with discordant results were available for confirmation at CDC. Four had non-reactive confirmatory test results that implied RT-1 false reactivity; one had ambiguous confirmatory test results which was non-reactive in further testing. Regardless of order and type of RT used, RTAs demonstrated high concordant results in the population surveyed. Additional laboratory testing on DBS following discordant results confirmed no infection. Implementing RTAs in the context of anonymous venue-based HIV testing could be an option when laboratory follow-up is not practicable.

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