Dataset Information

Pooled analysis of LAMP assay for the diagnosis of norovirus infection.

ABSTRACT:

Background

Rapid laboratory detection is essential to diagnose norovirus infection. LAMP has many advantages compared with RT-PCR for detecting norovirus, including high sensitivity, high specificity, rapidity, low cost, and intuitive results, which can be easily read with the naked eye with the help of color-based reporters. In this study, we intend to analyze the accuracy of LAMP methods for the diagnosis of norovirus infection.

Methods

Two researchers independently retrieved relevant literature up to January 2021 (PubMed, Web of Science, Cochrane Library, Embase, CNKI, Wan Fang, and VIP). The researchers screened all articles and extracted their research data for meta-analysis. QUADAS-2 tool was used to evaluate the quality of the included studies by Review Manager 5.3. Forest plots were performed by Meta-DiSc 1.4 to evaluate the accuracy of the test. Deeks' funnel plot symmetry tests were conducted by Stata 15.0 to check the potential publication bias.

Results

Eleven sets of data extracted from the eight included studies were included for meta-analysis. For the detection of norovirus, the pooled sensitivity, specificity, positive LR, negative LR, diagnostic OR, and their 95% CI were 0.96 (0.95-0.97), 0.99 (0.99-1.00), 91.14 (31.88-260.56), 0.06 (0.04-0.09), and 1473.68 (562.96-3857.70), respectively. Besides, AUC in the SROC curve was 0.9920.

Conclusion

LAMP had high sensitivity and specificity in terms of the diagnosis of norovirus infection. However, further extension of this approach should be researched to ensure the accuracy and practicability of this hopeful test in the future.

SUBMITTER: Qian XF

PROVIDER: S-EPMC8418469 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundWest Africa has witnessed the unprecedented outbreak of Ebola virus disease (EVD). The Ebola virus (EBOV) can cause Ebola hemorrhagic fever, which is documented as the most deadly viral hemorrhagic fever in the world. RT-PCR had been suggested to be employed in the detection of Ebola virus; however, this method has high requirements for laboratory equipment and takes a long time to determine Ebola infection. Although Xpert Ebola is a fast and simple instrument for the detection of Ebola virus, its effect is still unclear. This study is aimed at evaluating the accuracy of Xpert Ebola in diagnosing Ebola virus infection.MethodsUsing the keywords "Xpert" and "Ebola virus", relevant studies were retrieved from the database of PubMed, Embase, Web of Science, and Cochrane. RT-PCR was employed as a reference standard to evaluate whether the study is eligible to be included in the meta-analysis. Data from these included studies were extracted by two independent assessors and were then analyzed by the Meta-DiSc 1.4 software to produce the heterogeneity of sensitivity (SEN), specificity (SP), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic advantage ratio (DOR) of the study. The results of pooled analysis were plotted, together with the summary receiver operating characteristic (SROC) curve plotted by calculating the area under the curve (AUC). Generated pooled summary estimates (95% CIs) were calculated for the evaluation of the overall accuracy of this study.ResultsFive fourfold tables were made from the four studies that were included in the meta-analysis. The pooled sensitivity of Xpert Ebola was 0.98 (95% confidence interval (CI) (0.95, 0.99)), and the pooled specificity was 0.98 (95% CI (0.97, 0.99)). The pooled values of positive likelihood ratio was 53.91 (95% CI (12.82, 226.79)), with negative likelihood ratio being 0.04 (95% CI (0.02, 0.08)) and diagnostic odds ratio being 2649.45 (95% CI (629.61, 11149.02)). The AUC was 0.9961.ConclusionsCompared with RT-PCR, Xpert Ebola has high sensitivity and specificity. Therefore, it is a valued alternative method for the clinical diagnosis of Ebola virus infection. However, the Xpert Ebola test is a qualitative test that does not provide quantitative testing of EBOV concentration. Whether it can completely replace other methods or not calls for further evidences.

Project description:BackgroundMalaria is a globally distributed infectious disease. According to the World Health Organization, Angola is one of the six countries that account for over half the global malaria burden in terms of both malaria cases and deaths. Diagnosis of malaria still depends on microscopic examination of thin and thick blood smears and rapid diagnostic tests (RDTs), which often lack analytical and clinical sensitivity. Molecular methods could overcome these disadvantages. The aim of this study was to evaluate, for the first time to our knowledge, the performance of a loop-mediated isothermal amplification (LAMP) for the diagnosis of malaria in an endemic area in Cubal, Angola, and to assess the reproducibility at a reference laboratory.MethodsA total of 200 blood samples from patients attended at Hospital Nossa Senhora da Paz, Cubal, Angola, were analysed for Plasmodium spp. detection by microscopy, RDTs, and LAMP. LAMP assay was easily performed in a portable heating block, and the results were visualized by a simple colour change. Subsequently, the samples were sent to a reference laboratory in Spain to be reanalysed by the same colorimetric LAMP assay and also in real-time LAMP format.ResultsIn field tests, a total of 67/200 (33.5%) blood samples were microscopy-positive for Plasmodium spp., 98/200 RDT positive, and 112/200 (56%) LAMP positive. Using microscopy as reference standard, field LAMP detected more microscopy-positive samples than RDTs (66/67; 98% vs. 62/67; 92.5%). When samples were reanalysed at a reference laboratory in Spain using both colorimetric and real-time assays, the overall reproducibility achieved 84.5%.ConclusionsThis is the first study to our knowledge in which LAMP has been clinically evaluated on blood samples in a resource-poor malaria-endemic area. The colorimetric LAMP proved to be more sensitive than microscopy and RDTs for malaria diagnosis in field conditions. Furthermore, LAMP showed an acceptable level of reproducibility in a reference laboratory. The possibility to use LAMP in a real-time format in a portable device reinforces the reliability of the assay for molecular diagnosis of malaria in resource-poor laboratories in endemic areas.

Project description:BackgroundStrongyloides stercoralis, the chief causative agent of human strongyloidiasis, is a nematode globally distributed but mainly endemic in tropical and subtropical regions. Chronic infection is often clinically asymptomatic but it can result in severe hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. There is a great diversity of techniques used in diagnosing the disease, but definitive diagnosis is accomplished by parasitological examination of stool samples for morphological identification of parasite. Until now, no molecular method has been tested in urine samples as an alternative to stool samples for diagnosing strongyloidiasis. This study aimed to evaluate the use of a new molecular LAMP assay in a well-established Wistar rat experimental infection model using both stool and, for the first time, urine samples. The LAMP assay was also clinically evaluated in patients´ stool samples.Methodology/principal findingsStool and urine samples were obtained daily during a 28-day period from rats infected subcutaneously with different infective third-stage larvae doses of S. venezuelensis. The dynamics of parasite infection was determined by daily counting the number of eggs per gram of feces from day 1 to 28 post-infection. A set of primers for LAMP assay based on a DNA partial sequence in the 18S rRNA gene from S. venezuelensis was designed. The set up LAMP assay (namely, Strong-LAMP) allowed the sensitive detection of S. venezuelensis DNA in both stool and urine samples obtained from each infection group of rats and was also effective in S. stercoralis DNA amplification in patients´ stool samples with previously confirmed strongyloidiasis by parasitological and real-time PCR tests.Conclusions/significanceOur Strong-LAMP assay is an useful molecular tool in research of a strongyloidiasis experimental infection model in both stool and urine samples. After further validation, the Strong-LAMP could also be potentially applied for effective diagnosis of strongyloidiasis in a clinical setting.