Analytical performance of newly developed rapid point‐of‐care test for the simultaneous detection of hepatitis A, B, and C viruses in serum samples

Combining the detection of syphilis and HIV antibodies into one point-of-care test integrates syphilis screening into already existing HIV screening programs, which may be particularly beneficial in settings such as antenatal care. Using the INSTI Multiplex downward-flow immunoassay, we tested 200 stored serum samples from high-risk patients enrolled in a longitudinal study on HIV infection and syphilis in Peruvian men who have sex with men and transgender women. This rapid assay detected HIV andTreponema pallidumserum antibodies with sensitivities of 100% (95% confidence interval [CI], 95.9% to 100%) and 87.4% (95% CI, 81.4% to 92.0%), respectively, and specificities of 95.5% (95% CI, 89.9% to 98.5%) and 97.0% (95% CI, 84.2% to 99.9%), respectively (n= 200). The sensitivity for syphilis antibody detection was higher in patients with a rapid plasma reagin titer of ≥1:8 (97.3%) than in those with a titer of ≤1:4 (90%) or a nonreactive titer (66.7%).

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Comparative analysis of Truenat™ MTB Plus and Xpert® Ultra in diagnosing tuberculous meningitis

The International Journal of Tuberculosis and Lung Disease ◽

10.5588/ijtld.21.0156 ◽

2021 ◽

Vol 25 (8) ◽

pp. 626-631

Author(s):

K. Sharma ◽

M. Sharma ◽

M. Modi ◽

N. Singla ◽

A. Sharma ◽

...

Keyword(s):

Drug Resistance ◽

Cerebrospinal Fluid ◽

Comparative Analysis ◽

Tuberculous Meningitis ◽

Primary Healthcare ◽

Point Of Care ◽

Diagnostic Delay ◽

Simultaneous Detection ◽

Large Cohort ◽

Point Of Care Test

BACKGROUND: Diagnostic delay and drug resistance not only worsen the outcomes of tuberculous meningitis (TBM), but are also important impediments to TB elimination efforts. Given the need for a near point-of-care test suitable for primary healthcare centres and simultaneous detection of resistance, Truenat™ MTB Plus assay was evaluated on a large cohort of TBM patients.METHODS: Truenat assay was performed on 148 cerebrospinal fluid specimens (76 definite TBM, 32 probable TBM and 40 non-TBM controls) and its performance was compared with Xpert® Ultra.RESULTS: The overall sensitivity of Truenat and Ultra was respectively 78.7% and 67.6% in diagnosing TBM, and respectively 85.5% and 96% in diagnosing definite TBM. Twenty-three additional cases were detected using Truenat and 11 using Ultra. Truenat missed seven cases of rifampicin (RIF) resistance and indicated false RIF resistance in four cases.CONCLUSION: Performance of Truenat was comparable to that of Ultra in diagnosing TBM and inferior to Xpert Ultra in determining RIF resistance.

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Direct and Indirect Proof of SARS-CoV-2 Infections in Indigenous Wiwa Communities in North-Eastern Colombia—A Cross-Sectional Assessment Providing Preliminary Surveillance Data

Vaccines ◽

10.3390/vaccines9101120 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1120

Author(s):

Gustavo Concha ◽

Hagen Frickmann ◽

Anke Oey ◽

Monika Strengert ◽

Lothar Kreienbrock ◽

...

Keyword(s):

Point Of Care ◽

Indigenous Communities ◽

Serum Samples ◽

Cross Sectional ◽

Vaccination Programs ◽

Point Of Care Test ◽

North Eastern ◽

Nasal Swabs ◽

Study Participants ◽

Rapid Antibody

To provide initial data on local SARS-CoV-2 epidemiology and spread in indigenous communities in north-eastern Colombia, respiratory swabs and serum samples from volunteers of indigenous communities were examined in March and April 2021. Samples from non-indigenous Colombians from the same villages were included as well. While previous exposure to SARS-CoV-2 was assessed by analysing serum samples for IgG and IgM with a rapid antibody point-of-care-test (POCT), screening for active infections was carried out with an antigen POCT test and real-time PCR from nasal swabs. In 380 indigenous and 72 non-indigenous volunteers, 61 (13.5%) active infections and an additional 113 (25%) previous infections were identified using diagnostic serology and molecular assays. Previous infections were more frequent in non-indigenous volunteers, and relevant associations of clinical features with active or previous SARS-CoV-2 infections were not observed. Symptoms reported were mild to moderate. SARS-CoV-2 was frequent in the assessed Colombian indigenous communities, as 38.5% of the study participants showed signs of exposure to SARS-CoV-2, which confirms the need to include these indigenous communities in screening and vaccination programs.

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Laboratory diagnosis of human brucellosis in Egypt and persistence of the pathogen following treatment

The Journal of Infection in Developing Countries ◽

10.3855/jidc.1538 ◽

2011 ◽

Vol 5 (11) ◽

pp. 786-791 ◽

Cited By ~ 13

Author(s):

Ayman Marei ◽

Ghada Boghdadi ◽

Nahla Abdel-Hamed ◽

Rasha Hessin ◽

Theresia Abdoel ◽

...

Keyword(s):

Point Of Care ◽

Public Health Problem ◽

Laboratory Diagnosis ◽

Diagnostic Value ◽

Lateral Flow ◽

Lateral Flow Assay ◽

Human Brucellosis ◽

Major Public Health Problem ◽

Serum Samples ◽

Point Of Care Test

Introduction: Brucellosis is a major public health problem in Egypt. The Brucella IgM/IgG lateral flow assay was developed as a point-of-care test for the diagnosis of human brucellosis. The aim of this study was to assess the diagnostic value of the lateral flow assay for use in Egypt. Methodology: Fifty samples of patients who presented with clinical suspicion of brucellosis over a one-year period were collected. All samples were subjected to the Brucella IgM/IgG lateral flow assay, serum agglutination test (SAT), rose bengal RB Test (RB), 2- mercapteoethanol (2-ME), culture and PCR. SAT, 2- ME, culture and PCR were retested after the end of the treatment. Results: Culture and SAT confirmed the diagnosis of brucellosis in twenty patients. While 90% of the samples were positive by SAT, only 30% and 85% were positive by culture and PCR respectively. The sensitivity of the lateral flow assay calculated for the Brucella IgM/IgG was 95% and specificity was 97%. Conclusion: These data show that the lateral flow assay is more suitable for diagnosis of brucellosis in Egypt than culture and SAT. Application of the PCR on serum samples collected during follow-up revealed that the DNA of the pathogen was yet not completely cleared almost 60 days after the start of treatment with doxycycline and ciprofloxacin.

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Lateral Flow Aptasensor for Simultaneous Detection of Platelet-Derived Growth Factor-BB (PDGF-BB) and Thrombin

Molecules ◽

10.3390/molecules24040756 ◽

2019 ◽

Vol 24 (4) ◽

pp. 756 ◽

Cited By ~ 2

Author(s):

Guodong Liu ◽

Anant Gurung ◽

Wanwei Qiu

Keyword(s):

Growth Factor ◽

Point Of Care ◽

Low Cost ◽

Simultaneous Detection ◽

Lateral Flow ◽

Platelet Derived Growth Factor ◽

Great Promise ◽

Serum Samples ◽

Lateral Flow Strip ◽

Assay Time

Here we report a lateral flow aptasensor (LFA) for the simultaneous detection of platelet-derived growth factor-BB (PDGF-BB) and thrombin. Two pairs of aptamers, which are specific against PDGF-BB and thrombin, respectively, were used to prepare the LFA. Thiolated aptamers were immobilized on a gold nanoparticle (AuNP) surface and biotinylated aptamers were immobilized on the test zones of an LFA nitrocellulose membrane. The assay involved the capture of PDGF-BB and thrombin simultaneously in sandwich-type formats between the capture aptamers on the test zones of LFA and AuNP-labeled detection aptamers. AuNPs were thus captured on the test zones of the LFA and gave red bands to enable the visual detection of target proteins. Quantitative results were obtained by reading the test band intensities with a portable strip reader. By combining the highly specific molecular recognition properties of aptamers with the unique properties of lateral flow assay (low-cost, short assay time and a user-friendly format), the optimized aptasensor was capable of simultaneously detecting 1.0 nM of PDGF-BB and 1.5 nM of thrombin in association with a 10-min assay time. The biosensor was also successfully applied to detect PDGF-BB and thrombin in spiked human serum samples. The LFA shows great promise for the development of aptamer-based lateral flow strip biosensors for point-of-care or for the in-field detection of disease-related protein biomarkers.

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Evaluation of an Immunochromatographic Point-of-Care Test for the Simultaneous Detection of Nontreponemal and Treponemal Antibodies in Patients With Syphilis

Sexually Transmitted Diseases ◽

10.1097/olq.0000000000000161 ◽

2014 ◽

Vol 41 (8) ◽

pp. 467-469 ◽

Cited By ~ 4

Author(s):

Rita Castro ◽

Ângela Lopes ◽

Filomena da Luz Martins Pereira

Keyword(s):

Point Of Care ◽

Simultaneous Detection ◽

Point Of Care Test

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Multiplex Molecular Point-of-Care Test for Syndromic Infectious Diseases

BioChip Journal ◽

10.1007/s13206-021-00004-5 ◽

2021 ◽

Vol 15 (1) ◽

pp. 14-22

Author(s):

Hanbi Kim ◽

Hee Jae Huh ◽

Eunkyoung Park ◽

Doo-Ryeon Chung ◽

Minhee Kang

Keyword(s):

Infectious Diseases ◽

Point Of Care ◽

Simultaneous Detection ◽

Specific Treatment ◽

Care Level ◽

Primary Care Level ◽

Practical Applications ◽

Point Of Care Test ◽

Syndromic Approach ◽

Point Of Care Tests

AbstractPoint-of-care (POC) molecular diagnostics for clinical microbiology and virology has primarily focused on the detection of a single pathogen. More recently, it has transitioned into a comprehensive syndromic approach that employs multiplex capabilities, including the simultaneous detection of two or more pathogens. Multiplex POC tests provide higher accuracy to for actionable decisionmaking in critical care, which leads to pathogen-specific treatment and standardized usages of antibiotics that help prevent unnecessary processes. In addition, these tests can be simple enough to operate at the primary care level and in remote settings where there is no laboratory infrastructure. This review focuses on state-of-the-art multiplexed molecular point-of-care tests (POCT) for infectious diseases and efforts to overcome their limitations, especially related to inadequate throughput for the identification of syndromic diseases. We also discuss promising and imperative clinical POC approaches, as well as the possible hurdles of their practical applications as front-line diagnostic tests.

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Novel Point-of-Care Test for Simultaneous Detection of Nontreponemal and Treponemal Antibodies in Patients with Syphilis

Journal of Clinical Microbiology ◽

10.1128/jcm.00624-10 ◽

2010 ◽

Vol 48 (12) ◽

pp. 4615-4619 ◽

Cited By ~ 67

Author(s):

Arnold R. Castro ◽

Javan Esfandiari ◽

Shailendra Kumar ◽

Matthew Ashton ◽

Susan E. Kikkert ◽

...

Keyword(s):

Point Of Care ◽

Simultaneous Detection ◽

Point Of Care Test

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The performance of the Alere HIV combo point-of-care test on stored serum samples; useful for detection of early HIV-1 infections?

Sexually Transmitted Infections ◽

10.1136/sextrans-2016-052818 ◽

2017 ◽

Vol 94 (5) ◽

pp. 331-333 ◽

Cited By ~ 6

Author(s):

Carla van Tienen ◽

Sharona Rugebregt ◽

Sandra Scherbeijn ◽

Hannelore Götz ◽

Corine Geurts van Kessel

Keyword(s):

Hiv Infection ◽

Point Of Care ◽

Acute Infection ◽

Rapid Test ◽

Public Health Department ◽

Laboratory Setting ◽

Serum Samples ◽

Point Of Care Test ◽

P24 Antigen ◽

Hiv 1

IntroductionThe Alere HIV-1/2 Antigen/Antibody Combo point-of-care test is a commercially available 4th-generation rapid test for the diagnosis of HIV infection, including acute infection. We evaluated the sensitivity of this test in samples from patients with acute, recent or chronic HIV-1 infection.MethodsA validation of the test was performed using 89 HIV-positive serum samples collected in 2008–2016, that were stored at −20°C. Twenty-three samples were only p24-positive (acute infection); 49 samples were antibody-positive and p24-positive (recent infection); 17 samples were only antibody-positive (chronic infection). HIV infection was confirmed by standard-of-care assays and PCR. Samples came from patients attending an outpatient clinic for STDs at the Public Health Department and from patients within the Erasmus Medical Center, Rotterdam, the Netherlands.ResultsThe overall sensitivity of the test for diagnosing HIV infection based on detection of p24 antigen and/or antibodies was 92% (95% CI 86% to 98%) (82/89). In acute sera with only p24 antigen positivity, the sensitivity of the test decreased to 65% (95% CI 46% to 85%) (15/23). When both antibody and antigen testing were positive, the p24 sensitivity was only 24% (95% CI 12% to 36%) (12/49), but in these sera the final test result was positive in all sera (49/49) due to the positive antibody component.ConclusionsIn a laboratory setting, this test has an overall sensitivity of 92% to detect any stage of HIV-1 infection using sera specimens. It performs relatively well in detecting early HIV and may be beneficial as an initial screening in patients with a recent exposure to HIV. Additional testing in a laboratory setting remains mandatory as a proportion of acute HIV-1 infections are missed with this test.

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Validation and Optimization of Host Immunological Bio-Signatures for a Point-of-Care Test for TB Disease

Frontiers in Immunology ◽

10.3389/fimmu.2021.607827 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hygon Mutavhatsindi ◽

Gian D. van der Spuy ◽

Stephanus T. Malherbe ◽

Jayne S. Sutherland ◽

Annemieke Geluk ◽

...

Keyword(s):

Point Of Care ◽

Diagnostic Techniques ◽

World Health ◽

Hiv Positive ◽

Prior History ◽

Study Cohort ◽

Serum Samples ◽

Point Of Care Test ◽

History Of ◽

Triage Test

The development of a non-sputum-based, point-of-care diagnostic test for tuberculosis (TB) is a priority in the global effort to combat this disease, particularly in resource-constrained settings. Previous studies have identified host biomarker signatures which showed potential, but there is a need to validate and refine these for development as a test. We recruited 1,403 adults presenting with symptoms suggestive of pulmonary TB at primary healthcare clinics in six countries from West, East and Southern Africa. Of the study cohort, 326 were diagnosed with TB and 787 with other respiratory diseases, from whom we randomly selected 1005 participants. Using Luminex® technology, we measured the levels of 20 host biomarkers in serum samples which we used to evaluate the diagnostic accuracy of previously identified and novel bio-signatures. Our previously identified seven-marker bio-signature did not perform well (sensitivity: 89%, specificity: 60%). We also identified an optimal, two-marker bio-signature with a sensitivity of 94% and specificity of 69% in patients with no history of previous TB. This signature performed slightly better than C-reactive protein (CRP) alone. The cut-off value for a positive diagnosis differed for human immuno-deficiency virus (HIV)-positive and -negative individuals. Notably, we also found that no signature was able to diagnose TB adequately in patients with a prior history of the disease. We have identified a two-marker, pan-African bio-signature which is more robust than CRP alone and meets the World Health Organization (WHO) target product profile requirements for a triage test in both HIV-negative and HIV-positive individuals. This signature could be incorporated into a point-of-care device, greatly reducing the necessity for expensive confirmatory diagnostics and potentially reducing the number of cases currently lost to follow-up. It might also potentially be useful with individuals unable to provide sputum or with paucibacillary disease. We suggest that the performance of TB diagnostic signatures can be improved by incorporating the HIV-status of the patient. We further suggest that only patients who have never had TB be subjected to a triage test and that those with a history of previous TB be evaluated using more direct diagnostic techniques.

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