scholarly journals Feasibility and Operational Performance of Tuberculosis Detection by Loop-Mediated Isothermal Amplification Platform in Decentralized Settings: Results from a Multicenter Study

2016 ◽  
Vol 54 (8) ◽  
pp. 1984-1991 ◽  
Author(s):  
Christen M. Gray ◽  
Achilles Katamba ◽  
Pratibha Narang ◽  
Jorge Giraldo ◽  
Carlos Zamudio ◽  
...  
Keyword(s):  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Smear Microscopy ◽  
Eligibility Criteria ◽  
Loop Mediated Isothermal Amplification ◽  
Root Cause ◽  
Operational Characteristics ◽  
Reaction Volumes ◽  
Nonspecific Amplification ◽  
Eiken Chemical

Currently available nucleic acid amplification platforms for tuberculosis (TB) detection are not designed to be simple or inexpensive enough to implement in decentralized settings in countries with a high burden of disease. The loop-mediated isothermal amplification platform (LAMP) may change this. We conducted a study in adults with symptoms suggestive of TB in India, Uganda, and Peru to establish the feasibility of using TB-LAMP (Eiken Chemical Co.) in microscopy laboratories compared with using smear microscopy against a reference standard of solid and liquid cultures. Operational characteristics were evaluated as well. A total of 1,777 participants met the eligibility criteria and were included for analysis. Overall, TB-LAMP sensitivities among culture-positive samples were 97.2% (243/250; 95% confidence interval [CI], 94.3% to 98.2%) and 62.0% (88/142; 95% CI, 53.5% to 70.0%) for smear-positive and smear-negative TB, respectively, but varied widely by country and operator. Specificities ranged from 94.5% (446/472; 95% CI, 92.0% to 96.4%) to 98.0% (350/357; 95% CI, 96.0% to 99.2%) by country. A root cause analysis identified high temperatures, high humidity, and/or low reaction volumes as possible causes for false-positive results, as they may result in nonspecific amplification. The study was repeated in India with training focused on vulnerable steps and an updated protocol; 580 participants were included for analysis. Specificity in the repeat trial was 96.6% (515/533; 95% CI, 94.7% to 97.9%). To achieve acceptable performance of LAMP at the microscopy center level, significant training and infrastructure requirements are necessary.

scholarly journals Development of an in-house loop-mediated isothermal amplification (LAMP) assay for detection of Mycobacterium tuberculosis and evaluation in sputum samples of Nepalese patients

2008 ◽  
Vol 57 (4) ◽  
pp. 439-443 ◽  
Author(s):  
Basu Dev Pandey ◽  
Ajay Poudel ◽  
Tomoko Yoda ◽  
Aki Tamaru ◽  
Naozumi Oda ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Lamp Assay ◽  
High Sensitivity ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Lamp Method ◽  
Rrna Gene ◽  
Predictive Values ◽  
Loop Mediated Isothermal Amplification ◽  
System A

A number of nucleic acid amplification assays (NAAs) have been employed to detect tubercle bacilli in clinical specimens for tuberculosis (TB) diagnosis. Among these, loop-mediated isothermal amplification (LAMP) is an NAA possessing superior isothermal reaction characteristics. In the present study, a set of six specific primers targeting the Mycobacterium tuberculosis 16S rRNA gene with high sensitivity was selected and a LAMP system (MTB-LAMP) was developed. Using this system, a total of 200 sputum samples from Nepalese patients were investigated. The sensitivity of MTB-LAMP in culture-positive samples was 100 % (96/96), and the specificity in culture-negative samples was 94.2 % (98/104, 95 % confidence interval 90.5–97.9 %). The positive and negative predictive values of MTB-LAMP were 94.1 and 100 %, respectively. These results indicate that this MTB-LAMP method may prove to be a powerful tool for the early diagnosis of TB.

scholarly journals Feasibility and Performance of Loop-Mediated Isothermal Amplification Assay in the Diagnosis of Pulmonary Tuberculosis in Decentralized Settings in Eastern China

2019 ◽  
Vol 2019 ◽  
pp. 1-4
Author(s):  
Zhongdong Wang ◽  
Haiyan Sun ◽  
Zhisheng Ren ◽  
Bai Xue ◽  
Jie Lu ◽  
...  
Keyword(s):  
Eastern China ◽  
Isothermal Amplification ◽  
Smear Microscopy ◽  
Loop Mediated Isothermal Amplification ◽  
Resource Limited ◽  
Control And Prevention ◽  
Amplification Assay ◽  
Smear Negative ◽  
And Performance ◽  
Culture Positive

Early diagnosis is essential for the control and prevention of tuberculosis (TB). The objective of this study was to investigate the feasibility and performance of loop-mediated isothermal amplification (LAMP) in the diagnosis of pulmonary TB in county-level microscopy centers in Qingdao, Eastern China. A total of 523 presumptive TB patients were consecutively recruited between July 2017 and April 2018, and 22 patients were excluded from the analysis. Of 102 culture-positive cases, TB-LAMP identified 91 cases, demonstrating a sensitivity of 89.2%. In comparison, the sensitivity of routine smear microscopy was 69.6% (71/102), which was significantly lower than that of TB-LAMP (P=0.001). In addition, TB-LAMP sensitivities in smear-positive and smear-negative samples were 98.6% and 67.7%, respectively. In conclusion, our data demonstrate that TB-LAMP outperforms conventional smear microscopy in TB diagnosis, which could be used as an alternative method for smear microscopy in resource-limited settings in China.

scholarly journals Loop Mediated Isothermal Amplification: Principles and Applications in Plant Virology

Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 461 ◽  
Author(s):  
Stefano Panno ◽  
Slavica Matić ◽  
Antonio Tiberini ◽  
Andrea Giovanni Caruso ◽  
Patrizia Bella ◽  
...  
Keyword(s):  
Plant Protection ◽  
Point Of Care ◽  
Low Cost ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Plant Virology ◽  
Food Industries ◽  
Loop Mediated Isothermal Amplification ◽  
Application Fields ◽  
Agriculture And Food

In the last decades, the evolution of molecular diagnosis methods has generated different advanced tools, like loop-mediated isothermal amplification (LAMP). Currently, it is a well-established technique, applied in different fields, such as the medicine, agriculture, and food industries, owing to its simplicity, specificity, rapidity, and low-cost efforts. LAMP is a nucleic acid amplification under isothermal conditions, which is highly compatible with point-of-care (POC) analysis and has the potential to improve the diagnosis in plant protection. The great advantages of LAMP have led to several upgrades in order to implement the technique. In this review, the authors provide an overview reporting in detail the different LAMP steps, focusing on designing and main characteristics of the primer set, different methods of result visualization, evolution and different application fields, reporting in detail LAMP application in plant virology, and the main advantages of the use of this technique.

scholarly journals Loop-Mediated Isothermal Amplification (LAMP) for Detection of Various Organisms: A Review

2017 ◽  
Vol 11 (2) ◽  
pp. 20-27
Author(s):  
Arifa Akram
Keyword(s):  
Nucleic Acid ◽  
High Specificity ◽  
Disease Diagnosis ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Lamp Method ◽  
Isolation And Identification ◽  
Strand Displacement Amplification ◽  
Loop Mediated Isothermal Amplification ◽  
Prophylactic Measures

Disease diagnosis is important for implementation of proper therapeutic and prophylactic measures. Traditionally, disease diagnosis was depends upon isolation and identification of the causative organisms. This was followed by serology and after that molecular method. Molecular tests are valuable when early diagnosis is important. For this purpose, nucleic acid amplification (PCR, nucleic acid sequence-based amplification, self-sustained sequence replication, strand displacement amplification) is one of the most valuable tools not only for the diagnosis of infectious diseases but also used in advanced level research. The Loop-Mediated Isothermal Amplification (LAMP) is a unique nucleic acid amplification technique for diagnosis of various pathogens introduced at 2000 by Notomi and his colleagues which is simple, easy, rapid and cost effective when compared to PCR due to its high specificity, sensitivity, and rapidity. It uses a set of six primers and a DNA polymerase with stranddisplacement activity. Major advantage of LAMP method is its cost-effectiveness as it can be done simply by using waterbath or heating block. Bangladesh J Med Microbiol 2017; 11 (2): 20-27

In vitro system for detection of prostate cancer markers by loop-mediated isothermal amplification

2020 ◽  
Vol 36 (1) ◽  
pp. 3-6
Author(s):  
J.A. Makarova
Keyword(s):  
Prostate Cancer ◽  
Lymph Nodes ◽  
Cell Lines ◽  
Negative Control ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Specific Marker ◽  
In Vitro System ◽  
Loop Mediated Isothermal Amplification

Loop-mediated isothermal amplification (LAMP) of nucleic acids enables detection of amplification products in 10-20 min after the reaction begins. An intraoperative method for detection of metastases in lymph nodes is based on LAMP and is called one-step nucleic acid amplification (OSNA). It allows rapid detection of the epithelial-specific marker KRT19 in lymph nodes. The standard protocol for OSNA was developed more than 10 years ago. Since that, a new version of the key enzyme involved in the reaction (Bst-polymerase) was obtained, but its use in OSNA remains unexplored. Moreover, the time has come to apply OSNA to the detection of other cancer types, in particular prostate cancer. The first step is to create an in vitro system that allows LAMP to be carried out on prostate cancer cell lines. Here, LAMP protocol for the new Bst 3.0 polymerase with optimized dNTPs concentration and without reverse transcriptase was developed, and cell lines (DU-145 for prostate cancer and Molt-4 for negative control) were selected. In summary, a new in vitro system for LAMP-based detection of prostate cancer marker KRT19 was developed. LAMP, OSNA, prostate cancer This work was supported by a grant from the President of the Russian Federation for state support of young Russian scientists (MK-1906.2019.4).

scholarly journals Clinical profiling and use of loop-mediated isothermal amplification assay for rapid detection of Mycobacterium tuberculosis from sputum

1970 ◽  
Vol 7 (2) ◽  
pp. 109-114 ◽  
Author(s):  
A Poudel ◽  
BD Pandey ◽  
B Lekhak ◽  
B Rijal ◽  
BR Sapkota ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Nucleic Acid ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Common Symptom ◽  
Bcg Vaccination ◽  
Loop Mediated Isothermal Amplification ◽  
16S Rna ◽  
Clinical Profiling

Background: Tuberculosis is a global health problem and the situation is worsening with newer incidences of drug resistance and HIV association. Diagnosis of tuberculosis can be done by many methods and test, culture of sputum being the ideal one. Nucleic acid amplification (NAA) assay are more time efficient one, that amplify and detect specific nucleic acid sequences allows rapid, sensitive and specific detection of M. tuberculosis in sputum samples. Objectives: The present study intends to compile the clinical presentations of the pulmonary tuberculosis (PTB) patients and to evaluate the efficacy of in-house loop-mediated isothermal amplification (LAMP) in detecting Mycobacterium tuberculosis in sputum samples by comparing with microscopy and culture. Materials and methods: Two hundred two sputum samples were collected from 202 patients at National Tuberculosis Center, Bhaktapur, Nepal. Complete clinical profiling, epidemiological data and record on BCG vaccination were noted and the samples were subjected for microscopy, culture and in-house LAMP with six primers specific for 16S RNA gene of Mycobacterium tuberculosis. Result: Of the 176 cases of clinical profiling, productive cough was most common symptom in 147 (83.52%), followed by chest pain 136 (77.27%), fever 133 (75.56%) and haemoptysis 61 (34.66%). There was a statistically significant association between BCG vaccination and development of TB (Χ2=5.33, P=0.02). Of 202 cases, 115 (56.93%) were chest X-ray positive, 101(50%) were direct smear-positive and 100 (49.51%) were culture positive. LAMP had a sensitivity of 97% and specificity of 94.12% while comparing with culture. In addition, its sensitivity and specificity were 91.09% and 89.11% respectively with reference to microscopy. Conclusion: As in our previous study, overall, the result of present study further confirms that the in-house LAMP is a simple, rapid, sensitive and specific DNA amplification technique for PTB diagnosis. Because of rapidity of microscopy and specificity of culture, in-house LAMP assay can be used as a very powerful and useful supplementary tool with complete clinical profiling of the patients for rapid diagnosis of TB in both AFB-positive and negative cases who are suspected as PTB in disease endemic country like Nepal. Key words: clinical profiling; Sputum; DNA; LAMP; M. tuberculosis; Nepal DOI: 10.3126/kumj.v7i2.2701 Kathmandu University Medical Journal (2009) Vol.7, No.2 Issue 26, 109-114

Rapid and Specific Detection of the Thermostable Direct Hemolysin Gene in Vibrio parahaemolyticus by Loop-Mediated Isothermal Amplification

2009 ◽  
Vol 72 (4) ◽  
pp. 748-754 ◽  
Author(s):  
JIRO NEMOTO ◽  
CHIYO SUGAWARA ◽  
KENJI AKAHANE ◽  
KEIJI HASHIMOTO ◽  
TADASHI KOJIMA ◽  
...  
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Enrichment Culture ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Nucleic Acid Amplification ◽  
Loop Mediated Isothermal Amplification ◽  
Alkaline Peptone Water ◽  
Peptone Water ◽  
Thermostable Direct Hemolysin ◽  
Tdh Gene

Several investigators have reported that thermostable direct hemolysin (TDH) and TDH-related hemolysin are important virulence factors of Vibrio parahaemolyticus, but it has been difficult to detect these factors rapidly in seafood and other environmental samples. A novel nucleic acid amplification method, termed the loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity and rapidity under isothermal conditions, was applied. In this study, we designed tdh gene-specific LAMP primers for detection of TDH-producing V. parahaemolyticus. The specificity of this assay was evaluated with 32 strains of TDH-producing V. parahaemolyticus, one strain of TDH-producing Grimontia hollisae, 10 strains of TDH-nonproducing V. parahaemolyticus, and 94 strains of TDH-nonproducing bacteria, and the sensitivity was high enough to detect one cell per test. Moreover, to investigate the detection of TDH-producing V. parahaemolyticus in oysters, the LAMP assay was performed with enrichment culture in alkaline peptone water of oyster samples inoculated with TDH-producing V. parahaemolyticus and TDH-nonproducing V. parahaemolyticus and V. alginolyticus after enrichment in alkaline peptone water. These results suggest that the LAMP assay targeting tdh gene has high sensitivity and specificity and is useful to detect TDH-producing V. parahaemolyticus in oyster after enrichment.

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