An evaluation of the diagnostic performance characteristics of the Yellow Fever IgM immunochromatographic rapid diagnostic test kit from SD Biosensor in Ghana

Yellow fever is endemic in Ghana and outbreaks occur periodically. The prodromal signs due to Yellow Fever Virus (YFV) infection are non-specific, making clinical signs unreliable as the sole criteria for diagnosis. Accurate laboratory confirmation of suspected yellow fever cases is therefore vital in surveillance programs. Reporting of ELISA IgM testing results by laboratories can delay due to late arrival of samples from the collection sites as well as limited availability of ELISA kits. In this study, the diagnostic performance characteristics of a rapid immunochromatographic Standard Q Yellow Fever IgM test kit (SD Biosensor) was evaluated for the rapid diagnosis of Yellow Fever infection in Ghana. A panel of 275 sera, comprising 81 confirmed YFV positives and 194 negatives were re-tested in this study using the Standard Q Yellow Fever IgM test kit. Using the CDC/WHO Yellow Fever IgM capture ELISA as a benchmark, the sensitivity, specificity and accuracy of the Standard Q Yellow Fever test kit were 96.3%, 97.9% and 97.5%, respectively. The false positivity rate was 5.1% and there was no cross-reactivity when the Standard Q Yellow Fever test kit was tested against dengue, malaria and hepatitis B and C positive samples. In addition, inter-reader variability and invalid rate were both zero. The results indicate that the diagnostic performance of the Standard Q Yellow Fever IgM test kit on serum or plasma is comparable to the serum IgM detection by ELISA and can be used as a point of care rapid diagnostic test kit for YFV infection in endemic areas.

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Accuracy of a multispecies rapid diagnostic test kit for detection of malarial parasite at the point of care in a low endemicity region

Transactions of the Royal Society of Tropical Medicine and Hygiene ◽

10.1016/j.trstmh.2009.04.011 ◽

2009 ◽

Vol 103 (12) ◽

pp. 1237-1244 ◽

Cited By ~ 16

Author(s):

M. Meena ◽

D. Joshi ◽

R. Joshi ◽

S. Sridhar ◽

S. Waghdhare ◽

...

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Point Of Care ◽

Malarial Parasite ◽

Test Kit

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Diagnostic performance of HRP2-only malaria rapid diagnostic test in Ghanaian pregnant women with asymptomatic peripheral blood infection: the case of First Response® test kit

Second Edition in 2020 of the HSI Journal Volume 1 Issue 2 Publication - Health Sciences Investigations Journal ◽

10.46829/hsijournal.2020.12.1.2.86-92 ◽

2020 ◽

Vol 1 (2) ◽

pp. 86-92

Author(s):

Joseph Osarfo ◽

Harry Tagbor ◽

Michael Alifragis ◽

Pascal Magnuess

Keyword(s):

Pregnant Women ◽

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Peripheral Blood ◽

Diagnostic Performance ◽

False Negative ◽

Malaria Rapid Diagnostic Test ◽

First Response ◽

Test Kit ◽

In Pregnancy

Background: The use of malaria rapid diagnostic test(RDT) enables targeted treatment that mitigates against the development of parasite drug resistance. With detection thresholds at ≥200 parasites/μL, their diagnostic performance in pregnant women may be challenging as asymptomatic infections with low parasite densities are common. Few data exist on the performance of histidine-rich protein-2 (HRP2) RDTs in Ghanaian pregnant women considering commonly occurring low parasite densities. Objective: The study sought to contribute more knowledge on test performance on First Response® test kit to guide the continuous evaluation of HRP2 RDTs in pregnancy. Methods: As part of an antimalarial drug trial in pregnancy, First Response® RDT results were compared to microscopy of peripheral blood slides in 1664 women. The diagnostic performance indicators were computed as proportions with 95% confidence intervals. The risk of having a positive RDT result was computed for age, gravidity and parasite density using binomial regression methods. Results: Parasitaemia prevalence by microscopy was 5.71%(n =95/1664) while that by RDT was 21.57%(n = 359/1664). Sensitivity was 82.11% (n=78/95), specificity was 82.09% (n=1288/1569), positive predictive value was 21.73% (n=78/359), and the likelihood ratio for a positive test was 4.58. False-negative RDT results were recorded for low parasite densities as well as densities ≥ 200/ μL while false-positive results were recorded in 281of 1664 tests. Primigravidae and younger aged women were more likely to have positive RDT results compared to multigravidae and women aged ≥ 30 yr. Conclusion: The moderate sensitivity, specificity and other diagnostic parameters reported suggest the First Response® malaria RDT is useful for detecting peripheral parasitaemia in pregnant women but the use of HRP2-only RDTs is limited by the existence of parasites with HRP2 gene deletion. The use of RDTs based on combined antigens continues to be recommended. Further research is needed on RDT performance in pregnant women with declining malaria transmission.

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Rapid Diagnostic Test Kit for Point-of-Care Cerebrospinal Fluid Leak Detection

SLAS TECHNOLOGY Translating Life Sciences Innovation ◽

10.1177/2472630319877377 ◽

2019 ◽

Vol 25 (1) ◽

pp. 67-74

Author(s):

Daniel W. Bradbury ◽

Ashley E. Kita ◽

Kensuke Hirota ◽

Maie A. St. John ◽

Daniel T. Kamei

Keyword(s):

Cerebrospinal Fluid ◽

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Point Of Care ◽

Cerebrospinal Fluid Leak ◽

Leak Detection ◽

Csf Leak ◽

Medical Provider ◽

Test Kit ◽

Csf Leaks

Cerebrospinal fluid (CSF) leaks can occur when there is communication between the intracranial cavities and the external environment. They are a common and serious complication of numerous procedures in otolaryngology, and if not treated, persistent leaks can increase a patient’s risk of developing life-threatening complications such as meningitis. As it is not uncommon for patients to exhibit increased secretions postoperatively, distinguishing normal secretions from those containing CSF can be difficult. Currently, there are no proven, available tests that allow a medical provider concerned about a CSF leak to inexpensively, rapidly, and noninvasively rule out the presence of a leak. The gold standard laboratory-based test requires that a sample be sent to a tertiary site for analysis, where days to weeks may pass before results return. To address this, our group recently developed a semiquantitative, barcode-style lateral-flow immunoassay (LFA) for the quantification of the beta-trace protein, which has been reported to be an indicator of the presence of CSF leaks. In the work presented here, we created a rapid diagnostic test kit composed of our LFA, a collection swab, dilution buffers, disposable pipettes, and instructions. Validation studies demonstrated excellent predictive capabilities of this kit in distinguishing between clinical specimens containing CSF and those that did not. Our diagnostic kit for CSF leak detection can be operated by an untrained user, does not require any external equipment, and can be performed in approximately 20 min, making it well suited for use at the point of care. This kit has the potential to transform patient outcomes.

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Development and evaluation of a new IgM/IgG rapid diagnostic test for SARS-CoV-2

10.1101/2020.10.09.20209866 ◽

2020 ◽

Author(s):

P.J. Ducrest

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Gold Standard ◽

Diagnostic Performance ◽

Point Of Care ◽

Negative Control ◽

Simple Point ◽

Rt Pcr ◽

High Diagnostic Accuracy ◽

Plasma Displays

AbstractThere is an urgent need in rapid diagnostic test (RDT) to detect antibodies against SARS-CoV-2. We have developed a rapid and simple point-of-care lateral flow immunoassay (LFIA) detecting IgM and IgG against SARS-CoV-2 in 10 minutes. The aim of this study is to evaluate the diagnostic performance of this RDT. RT-PCR positive plasma samples (n=35) for SARS-CoV-2 and 97 negative control samples were studied. Diagnostic performance of IgG/IgM RDT was assessed using both gold standard RT-PCR and Electro-chemiluminescence immunoassay (ECLIA) Elecsys® Anti-SARS-CoV-2 total Ig. Overall, RDT sensitivity was 100% (95% confidence interval [95%CI]: 88-100%) and specificity 93% (95% CI: 85-97%). This IgG/IgM RDT done in plasma displays a high diagnostic accuracy for SARS-CoV-2 IgG/IgM in high COVID-19 prevalence settings. Its use could be considered in the absence of routine diagnostic serology facilities for samples collected between 10 and 180 days after symptoms onset.

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Diagnostic performance of an ultrasensitive HRP2-based malaria rapid diagnostic test kit used in surveys of afebrile people living in Southern Ghana

Malaria Journal ◽

10.1186/s12936-021-03665-7 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Festus K. Acquah ◽

Dickson Donu ◽

Evans K. Obboh ◽

Dorcas Bredu ◽

Bernice Mawuli ◽

...

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Diagnostic Performance ◽

Venous Blood ◽

Malaria Rapid Diagnostic Test ◽

Treatment Interventions ◽

Enhanced Sensitivity ◽

Test Kit ◽

Blood Smears ◽

Study Participants

Abstract Background The Alere™ Malaria Ag P.f Ultra-sensitive RDT (UsmRDT) kit is an HRP2-based malaria rapid diagnostic test (RDT) with enhanced sensitivity relative to the SD Bioline Malaria Ag P.f RDT (mRDT) kit. However, the diagnostic performance of the UsmRDT kit has not been evaluated in Ghana. Methods A total of 740 afebrile participants aged between 3 and 88 years old were recruited from the Central and Greater Accra Regions of Ghana during the off-peak malaria season. Axillary body temperature was measured, and a volume of 1 ml venous blood was drawn from each participant. Prior to separating the blood into plasma and packed cell pellets via centrifugation, the blood was spotted onto one UsmRDT and one mRDT kit and also used to prepare thick and thin blood smears as well as filter paper blood spots. Plasmodium falciparum specific polymerase chain reaction (PCR) was performed on gDNA extracted from 100 µl of the whole blood. Results The overall positivity rate for microscopy, PCR, UsmRDT and mRDT kit were 20.4%, 40.8%, 31.3% and 30.8%, respectively. Overall, the UsmRDT identified 9.3% (28/302) more PCR positive samples than the mRDT kits. All samples that were negative by the UsmRDT kit were also negative by the mRDT kit. Overall, the sensitivity and specificity of the UsmRDT was 73% (221/302) and 89% (388/436), respectively, while that for the mRDT kit was 58% and 90%, respectively. Conclusion Although the UsmRDT kit was not as sensitive as PCR at detecting asymptomatic P. falciparum carriage, it correctly identified P. falciparum in 9.3% of the study participants that were not captured by the mRDT kit. In malaria endemic settings, the UsmRDT would provide an added advantage by identifying more asymptomatic P. falciparum carriers than the mRDT kit for targeted treatment interventions.

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Performance evaluation of the Simtomax® CoronaCheck rapid diagnostic test

10.1101/2020.10.28.20219667 ◽

2020 ◽

Author(s):

P. J. Ducrest ◽

A. Freymond ◽

J.-M. Segura

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Diagnostic Performance ◽

High Sensitivity ◽

High Specificity ◽

Negative Control ◽

List Type ◽

Plasma Samples ◽

Rt Pcr ◽

Two Samples

AbstractThe aim of this study was to evaluate the diagnostic performance of Simtomax® CoronaCheck, a serology rapid diagnostic test (RDT) for the detection of IgG and IgM against SARS-CoV-2. 48 plasma samples positive for SARS-CoV-2 based on RT-PCR and 98 negative control samples were studied. Diagnostic performance of the IgG/IgM RDT was assessed against RT-PCR and the electro-chemiluminescence immunoassay (ECLIA) Elecsys® Anti-SARS-CoV-2 total Ig. Overall, the RDT sensitivity was 92% (95% confidence interval [95%CI]: 79-97), specificity 97% (95% CI: 91-99%), PPV 94% (95% CI: 81-98) and the NPV 96% (95% CI: 89-99). When considering only samples collected ≥ 15 days post-symptoms (DPS), the sensitivity increased to 98% (95%CI: 86-100) and the specificity was 97% (95% CI: 91-99%). Two samples with 180 DPS were still positive for IgG. Globally, this IgG/IgM RDT displayed a high diagnostic accuracy for SARS-CoV-2 IgG/IgM detection in plasma samples in high COVID-19 prevalence settings. It could be effectively used, in absence of facilities for routine diagnostic serology, for samples with a DPS between 15 and 180 days.Highlights–The rapid diagnostic test Simtomax CoronaCheck displays a high sensitivity of 98% and a high specificity of 97% for SARS-CoV-2 IgG/IgM detection in plasma samples after 15 days post-symptoms.–The rapid diagnostic test Simtomax CoronaCheck can detect SARS-CoV-2 antibodies in plasma up to 180 days after symptom onset.–The rapid diagnostic test Simtomax CoronaCheck could be effectively used as an alternative to serological analysis using laboratory facilities.

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OC 8173 RAPID DETECTION OF MYCOBACTERIUM ULCERANS BY RECOMBINASE POLYMERASE AMPLIFICATION

BMJ Global Health ◽

10.1136/bmjgh-2019-edc.2 ◽

2019 ◽

Vol 4 (Suppl 3) ◽

pp. A2.1-A2

Author(s):

Michael Frimpong ◽

Hubert Ahor ◽

Francisca Sarpong ◽

Ken Laing ◽

Mark Wansbrough-Jones ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Point Of Care ◽

Clinical Signs ◽

Buruli Ulcer ◽

Cross Reactivity ◽

Current Control ◽

Mycobacterium Ulcerans ◽

Recombinase Polymerase Amplification ◽

Clinical Samples ◽

Clinical Sensitivity

BackgroundThere are no primary measures to prevent people from contracting Buruli ulcer, mainly due to poor understanding of its epidemiology. The current control strategy emphasises early diagnosis and prompt treatment, with the goal of avoiding the complications associated with advanced stages of the disease. There is no diagnostic test for the disease appropriate for use at the primary health care level where most cases are detected and treated. Diagnosis based on clinical signs is unreliable in inexperienced hands and complicated by infections that have similar presentations. This study was to develop and evaluate the use of recombinase polymerase amplification (RPA) assay for the detection of Mycobacterium ulcerans at the point of patient care.MethodsA specific fragment of IS2404 of M. ulcerans was amplified in 15 min at a constant temperature of 42°C, using the RPA assay and analysed on a portable fluorometre. Themethod was tested for sensitivity and specificity with molecular standard of IS2404 DNA fragment, various M.ulcerans strains, other mycobacteria and environmentally associated bacteria. Additionally, the assay performance as a diagnostic tool was tested with archived DNA from symptomatic patients. All results were compared with that of a highly sensitive IS2404 PCR.ResultsThe detection limit was 50 copies of IS2404 in 15 min using plasmid standard and 125 fg with genomic Mu DNA equivalent 25 genomic copies. The assay was highly specific in detecting all strains of M. ulcerans with no observed cross reactivity with other mycobacteria and common skin colonising bacteria. The clinical sensitivity and specificity of the BU-RPA assay using clinical samples was 86% and 100% respectively.ConclusionWe have developed a real-time isothermal RPA assay for the detection of M. ulcerans as a cheaper alternative to PCR. Combining this assay with a simple extraction protocol will maximise its use as point-of-care test for Buruli ulcer.

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