Loop-Mediated Isothermal Amplification on Crude DNA as a Point-of-Care Test for the Diagnosis of Mycoplasma-Related Vaginitis During Early Pregnancy

The rampant spread of COVID-19 and the worldwide prevalence of infected cases demand a rapid, simple, and cost-effective Point of Care Test (PoCT) for the accurate diagnosis of this pandemic. The most common molecular tests approved by regulatory bodies across the world for COVID-19 diagnosis are based on Polymerase Chain Reaction (PCR). While PCR-based tests are highly sensitive, specific, and remarkably reliable, they have many limitations ranging from the requirement of sophisticated laboratories, need of skilled personnel, use of complex protocol, long wait times for results, and an overall high cost per test. These limitations have inspired researchers to search for alternative diagnostic methods that are fast, economical, and executable in low-resource laboratory settings. The discovery of Loop-mediated isothermal Amplification (LAMP) has provided a reliable substitute platform for the accurate detection of low copy number nucleic acids in the diagnosis of several viral diseases, including epidemics like Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). At present, a cocktail of LAMP assay reagents along with reverse transcriptase enzyme (Reverse Transcription LAMP, RT-LAMP) can be a robust solution for the rapid and cost-effective diagnosis for COVID-19, particularly in developing, and low-income countries. In summary, the development of RT-LAMP based diagnostic tools in a paper/strip format or the integration of this method into a microfluidic platform such as a Lab-on-a-chip may revolutionize the concept of PoCT for COVID-19 diagnosis. This review discusses the principle, technology and past research underpinning the success for using this method for diagnosing MERS and SARS, in addition to ongoing research, and the prominent prospect of RT-LAMP in the context of COVID-19 diagnosis.

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Loop-mediated isothermal amplification (LAMP) for malarial parasites of humans: Would it come to clinical reality as a point-of-care test?

Acta Tropica ◽

10.1016/j.actatropica.2012.02.004 ◽

2012 ◽

Vol 122 (3) ◽

pp. 233-240 ◽

Cited By ~ 65

Author(s):

Rashad Abdul-Ghani ◽

Abdulsalam M. Al-Mekhlafi ◽

Panagiotis Karanis

Keyword(s):

Point Of Care ◽

Isothermal Amplification ◽

Loop Mediated Isothermal Amplification ◽

Point Of Care Test ◽

Clinical Reality

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Loop-Mediated Isothermal Amplification in Schistosomiasis

Journal of Clinical Medicine ◽

10.3390/jcm10030511 ◽

2021 ◽

Vol 10 (3) ◽

pp. 511

Author(s):

Juan García-Bernalt Diego ◽

Pedro Fernández-Soto ◽

Begoña Febrer-Sendra ◽

Beatriz Crego-Vicente ◽

Antonio Muro

Keyword(s):

Point Of Care ◽

Therapy Monitoring ◽

Isothermal Amplification ◽

Diagnostic Methods ◽

Diagnostic Tools ◽

Intermediate Hosts ◽

Early 21St Century ◽

Loop Mediated Isothermal Amplification ◽

Advantages And Disadvantages ◽

Point Of Care Test

Human schistosomiasis is one of the most important parasitic diseases, causing around 250 million cases (mostly in Africa) and 280,000–500,000 deaths every year. Due to the limited resources and the far-removed nature of many endemic areas, the implementation of new, sensitive and specific diagnostic tools has had little success. This is particularly true for PCR-based molecular methods that require expensive equipment and trained personnel to be executed. Loop-mediated isothermal amplification (LAMP) along with other isothermal techniques appeared in the early 21st century as an alternative to those methods, overcoming some of the aforementioned limitations and achieving a more inexpensive diagnostic. However, to this date, neither LAMP nor any other isothermal technique have signified a meaningful change in the way schistosomiasis diagnosis is routinely performed. Here, we present the recent developments in LAMP-based schistosomiasis diagnosis. We expose the main advantages and disadvantages of LAMP technology over PCR and other classical diagnostic methods focusing in various research approaches on intermediate hosts, animal models and patients. We also examine its potential clinical application in post-therapy monitoring, as well as its usefulness as a point-of-care test.

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Performance and Application of Commercially Available Loop-Mediated Isothermal Amplification (LAMP) Kits in Malaria Endemic and Non-Endemic Settings

Diagnostics ◽

10.3390/diagnostics11020336 ◽

2021 ◽

Vol 11 (2) ◽

pp. 336

Author(s):

Ulrika Morris ◽

Berit Aydin-Schmidt

Keyword(s):

Point Of Care ◽

High Sensitivity ◽

Rapid Diagnostic Tests ◽

Isothermal Amplification ◽

Chain Reaction ◽

Loop Mediated Isothermal Amplification ◽

Point Of Care Test ◽

Search Terms ◽

Polymerase Chain ◽

Meta Analyses

Loop-mediated isothermal amplification (LAMP) is a sensitive molecular tool suitable for use as a near point-of-care test for the diagnosis of malaria. Recent meta-analyses have detailed high sensitivity and specificity of malaria LAMP when compared to microscopy, rapid diagnostic tests, and polymerase chain reaction in both endemic and non-endemic settings. Despite this, the use of malaria LAMP has primarily been limited to research settings to date. In this review, we aim to assess to what extent commercially available malaria LAMP kits have been applied in different settings, and to identify possible obstacles that may have hindered their use from being adopted further. In order to address this, we conducted a literature search in PubMed.gov using the search terms (((LAMP) OR (Loop-mediated isothermal amplification)) AND ((Malaria) OR (Plasmodium))). Focusing primarily on studies employing one of the commercially available kits, we then selected three key areas of LAMP application for further review: the performance and application of LAMP in malaria endemic settings including low transmission areas; LAMP for malaria screening during pregnancy; and malaria LAMP in returning travelers in non-endemic settings.

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Essential properties and pitfalls of colorimetric Reverse Transcription Loop-mediated Isothermal Amplification as a point-of-care test for SARS-CoV-2 diagnosis

Molecular Medicine ◽

10.1186/s10020-021-00289-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Bruna de Oliveira Coelho ◽

Heloisa Bruna Soligo Sanchuki ◽

Dalila Luciola Zanette ◽

Jeanine Marie Nardin ◽

Hugo Manuel Paz Morales ◽

...

Keyword(s):

Viral Load ◽

Internal Control ◽

Reverse Transcription ◽

Color Change ◽

Point Of Care ◽

Colorimetric Detection ◽

False Negative ◽

Isothermal Amplification ◽

Clinical Samples ◽

Loop Mediated Isothermal Amplification

Abstract Background SARS-CoV-2 Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) colorimetric detection is a sensitive and specific point-of-care molecular biology technique used to detect the virus in only 30 min. In this manuscript we have described a few nuances of the technique still not properly described in the literature: the presence of three colors clusters; the correlation of the viral load with the color change; and the importance of using an internal control to avoid false-negative results. Methods To achieve these findings, we performed colorimetric RT-LAMP assays of 466 SARS-CoV-2 RT-qPCR validated clinical samples, with color quantification measured at 434 nm and 560 nm. Results First we determinate a sensitivity of 93.8% and specificity of 90.4%. In addition to the pink (negative) and yellow (positive) produced colors, we report for the first time the presence of an orange color cluster that may lead to wrong diagnosis. We also demonstrated using RT-qPCR and RT-LAMP that low viral loads are related to Ct values > 30, resulting in orange colors. We also demonstrated that the diagnosis of COVID-19 by colorimetric RT-LAMP is efficient until the fifth symptoms day when the viral load is still relatively high. Conclusion This study reports properties and indications for colorimetric RT-LAMP as point-of-care for SARS-CoV-2 diagnostic, reducing false results, interpretations and optimizing molecular diagnostics tests application.

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