scholarly journals Amplification of cestode DNA from the peri-anal region of naturally infected foxes by PCR and LAMP: proof of concept for a potential sampling strategy for diagnosing human taeniosis

2021 ◽  
Author(s):  
Gillian Muchaamba ◽  
Cristian A. Alvarez Rojas ◽  
Peter Deplazes
Keyword(s):  
Reproductive Potential ◽  
Lamp Assay ◽  
Sampling Strategy ◽  
Turnaround Time ◽  
Sample Collection ◽  
Alkaline Lysis ◽  
Anal Region ◽  
Resource Limited ◽  
Multiplex Pcr Assay ◽  
Anal Swab

AbstractThe diagnosis of human taeniosis can be achieved through coproscopy, ELISA or PCR. An important limitation of these methods is the high turnaround time for stool sample collection and preparation, indicating the need for a straightforward sampling strategy. Due to the high metabolic activity and reproductive potential of Taenia spp., we hypothesise that parasite DNA (cells and eggs) present in the peri-anal region of the host can be exploited as a target for molecular diagnosis. We evaluated the feasibility of recovering parasite DNA from the peri-anal area of foxes naturally infected with Taenia spp. Before necropsy, cotton swabs were rubbed at the peri-anal region of foxes. DNA was extracted using alkaline lysis coupled with a commercial DNA isolation kit (method A) or alkaline lysis alone (method B). DNA was used in the multiplex-PCR assay (previously described and called here swab-PCR) and a novel LAMP assay detecting Taenia spp. commonly found in foxes (swab-LAMP). The results of these assays from 105 foxes were compared with the presence of intestinal helminths determined at necropsy and by the sedimentation and counting technique (SCT). The sensitivity of swab-PCR for detecting Taenia (n = 68) was 89.8% (95% CI, 77.7–96.6) and 89.5% (66.9–98.7) using methods A and B, respectively. The sensitivity of the swab-LAMP assay was 83.7% (70.3–92.7) using method A and 89.5% (66.9–98.7) with method B. We postulate that peri-anal swab sampling followed by simplified DNA extraction and LAMP might be a suitable strategy for surveillance of human taeniosis in resource-limited settings in the future.

scholarly journals A 3D-printed magnetic digital microfluidic diagnostic platform for rapid colorimetric sensing of carbapenemase-producing Enterobacteriaceae

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Pojchanun Kanitthamniyom ◽  
Pei Yun Hon ◽  
Aiwu Zhou ◽  
Mohammad Yazid Abdad ◽  
Zhi Yun Leow ◽  
...  
Keyword(s):  
Point Of Care ◽  
Resistance Mechanism ◽  
Turnaround Time ◽  
World Health ◽  
Colorimetric Sensing ◽  
Resource Limited ◽  
Reaction Chambers ◽  
Technological Platform ◽  
Health Organization ◽  
Digital Microfluidic

AbstractCarbapenemase-producing Enterobacteriaceae (CPE) are a group of drug-resistant Gram-negative pathogens that are classified as a critical threat by the World Health Organization (WHO). Conventional methods of detecting antibiotic-resistant pathogens do not assess the resistance mechanism and are often time-consuming and laborious. We have developed a magnetic digital microfluidic (MDM) platform, known as MDM Carba, for the identification of CPE by measuring their ability to hydrolyze carbapenem antibiotics. MDM Carba offers the ability to rapidly test CPE and reduce the amount of reagents used compared with conventional phenotypic testing. On the MDM Carba platform, tests are performed in droplets that function as reaction chambers, and fluidic operations are accomplished by manipulating these droplets with magnetic force. The simple droplet-based magnetic fluidic operation allows easy system automation and simplified hands-on operation. Because of the unique “power-free” operation of MDM technology, the MDM Carba platform can also be operated manually, showing great potential for point-of-care testing in resource-limited settings. We tested 27 bacterial isolates on the MDM Carba platform, and the results showed sensitivity and specificity that were comparable to those of the widely used Carba NP test. MDM Carba may shorten the overall turnaround time for CPE identification, thereby enabling more timely clinical decisions for better clinical outcomes. MDM Carba is a technological platform that can be further developed to improve diagnostics for other types of antibiotic resistance with minor modifications.

scholarly journals Colorimetric Reverse Transcription–Loop-Mediated Isothermal Amplification Assay for Rapid Detection of SARS-CoV-2

2021 ◽  
Author(s):  
Meng Yee Lai ◽  
Soo Nee Tang ◽  
Yee Ling Lau
Keyword(s):  
Sensitivity And Specificity ◽  
Reverse Transcription ◽  
Virus Detection ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Clinical Sensitivity ◽  
Loop Mediated Isothermal Amplification ◽  
Resource Limited ◽  
Detection Technology ◽  
Simple Detection

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been spreading rapidly all over the world. In the absence of effective treatments or a vaccine, there is an urgent need to develop a more rapid and simple detection technology of COVID-19. We describe a WarmStart colorimetric reverse transcription–loop-mediated isothermal amplification (RT-LAMP) assay for the detection of SARS-CoV-2. The detection limit for this assay was 1 copy/µL SARS-CoV-2. To test the clinical sensitivity and specificity of the assay, 37 positive and 20 negative samples were used. The WarmStart colorimetric RT-LAMP had 100% sensitivity and specificity. End products were detected by direct observation, thereby eliminating the need for post-amplification processing steps. WarmStart colorimetric RT-LAMP provides an opportunity to facilitate virus detection in resource-limited settings without a sophisticated diagnostic infrastructure.

scholarly journals Novel Multiplex and Loop-Mediated Isothermal Amplification (LAMP) Assays for Rapid Species and Mating-Type Identification of Oculimacula acuformis and O. yallundae (Causal Agents of Cereal Eyespot), and Application for Detection of Ascospore Dispersal and in planta Use

2020 ◽  
Author(s):  
Kevin M. King ◽  
Gavin J. Eyres ◽  
Jon West ◽  
Clara Siraf ◽  
Pavel Matusinsky ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Mating Type ◽  
Field Experiments ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
In Planta ◽  
Loop Mediated Isothermal Amplification ◽  
Multiplex Pcr Assay ◽  
Species Specific ◽  
Oculimacula Acuformis

Eyespot, caused by the related fungal pathogens Oculimacula acuformis (OA) and O. yallundae (OY), is an important cereal stem-base disease in temperate parts of the world. Both species are dispersed mainly by splash-dispersed conidia but are also known to undergo sexual reproduction yielding apothecia containing ascospores. Field diagnosis of eyespot can be challenging with other pathogens causing similar symptoms, which complicates eyespot management strategies. Differences between OA and OY (e.g. host pathogenicity and fungicide sensitivity) require that both be targeted for effective disease management. Here, we develop and apply two molecular methods for species-specific and mating-type (MAT1-1 or MAT1-2) discrimination of OA and OY isolates. First, a multiplex PCR-based diagnostic assay targeting the MAT idiomorph region was developed allowing simultaneous determination of both species and mating type. This multiplex-PCR assay was successfully applied to type a global collection of isolates. Second, the development of loop-mediated isothermal amplification (LAMP) assays targeting beta-tubulin sequences is described, which allow fast (<9 min) species-specific discrimination of global OA and OY isolates. The LAMP assay can detect very small amounts of target DNA (1 pg) and was successfully applied in planta. In addition, mating-type specific LAMP assays were also developed for rapid (<12 min) genotyping of OA and OY isolates. Finally, the multiplex PCR-based diagnostic was applied, in conjunction with spore trapping in field experiments, to provide evidence of the wind dispersal of ascospores from a diseased crop. The results indicate an important role of the sexual cycle in the dispersal of eyespot.

scholarly journals 1774. Impact of a Multiplex Polymerase Chain Reaction Assay on the Clinical Management of Adults Undergoing a Lumbar Puncture for Suspected Community-Onset Central Nervous System Infections

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S654-S654
Author(s):  
Matthew Moffa ◽  
Rawiya Elrufay ◽  
Thomas L Walsh ◽  
Dustin R Carr ◽  
Nathan Shively ◽  
...  
Keyword(s):  
Multiplex Polymerase Chain Reaction ◽  
Intervention Group ◽  
Turnaround Time ◽  
Cns Infection ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Post Intervention ◽  
Multiplex Pcr Assay ◽  
Polymerase Chain ◽  
Post Intervention Group

Abstract Background Patients admitted from the community with a suspected central nervous system (CNS) infection require prompt antimicrobial treatment and diagnostic evaluation. Our health network recently implemented a multiplex polymerase chain reaction (PCR) assay in-house. Methods This was a pre-/post-intervention study evaluating the impact that a multiplex PCR assay had on the clinical management of patients ≥18 years of age admitted from the community with a lumbar puncture (LP) performed for a suspected CNS infection. The primary outcome was Herpes Simplex Virus (HSV) PCR turnaround time (TAT). Secondary outcomes included inpatient length of stay (LOS), total antimicrobial days of therapy (DOT), and antiviral DOT. Patients were excluded if an LP was performed after hospital day 3, if they were on a systemic antimicrobial for a non-CNS indication, if they were a neurosurgical patient, and if they had a fungal CNS infection. Results The pre- and post-intervention groups each had 57 patients. The average age was 51 and 52 years in the pre- and post-intervention groups, respectively. Four patients (7%) in the pre-intervention group were immunocompromised, compared with 9 (16%) in the post-intervention group. Four patients in the pre-intervention group had a positive PCR assay for either HSV or Varicella Zoster Virus (VZV), compared with 5 patients in the post-intervention group. Neither group had a positive cerebrospinal fluid culture, bacterial antigen assay, or bacterial PCR assay. The median (IQR) HSV PCR TAT was significantly longer in the pre-intervention group, 85 (78, 96) vs. 3.9 hours (2.9, 4.7), P < 0.001. The mean LOS was numerically greater in the pre-intervention arm (7 vs. 4.7 days, P = 0.069), as were the total antimicrobial DOT (9 vs. 7.4 days, P = 0.279) and antiviral DOT (3.9 vs. 2.7 days, P = 0.136). Pre-intervention antiviral DOT was significantly greater (3.1 vs. 1.6 days, P = 0.011) in patients without a positive HSV or VZV PCR. Conclusion Implementing a multiplex PCR assay for adults undergoing an LP for a suspected CNS infection significantly reduced the HSV PCR turnaround time. Antiviral DOT was significantly shorter in patients with a negative PCR result post-intervention. We also found a non-significant reduction in LOS, total antimicrobial DOT, and antiviral DOT. Disclosures All authors: No reported disclosures.

Evaluation of two point of care technologies for measuring monoclonal antibody therapeutic-A concentrations in blood

Bioanalysis ◽  
2020 ◽  
Vol 12 (20) ◽  
pp. 1449-1458
Author(s):  
Saloumeh K Fischer ◽  
Kathi Williams ◽  
Ian Harmon ◽  
Bryan Bothwell ◽  
Hua Xu ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Real Time ◽  
Point Of Care ◽  
Turnaround Time ◽  
Monitoring Methods ◽  
Sample Collection ◽  
Time Data ◽  
Serum Samples ◽  
Quick Turnaround Time

Aim: Current blood monitoring methods require sample collection and testing at a central lab, which can take days. Point of care (POC) devices with quick turnaround time can provide an alternative with faster results, allowing for real-time data leading to better treatment decisions for patients. Results/Methodology: An assay to measure monoclonal antibody therapeutic-A was developed on two POC devices. Data generated using 75 serum samples (65 clinical & ten spiked samples) show correlative results to the data generated using Gyrolab technology. Conclusion: This case study uses a monoclonal antibody therapeutic-A concentration assay as an example to demonstrate the potential of POC technologies as a viable alternative to central lab testing with quick results allowing for real-time decision-making.

scholarly journals Artificial Intelligence-Assisted Loop Mediated Isothermal Amplification (AI-LAMP) for Rapid Detection of SARS-CoV-2

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 972 ◽  
Author(s):  
Mohammed A. Rohaim ◽  
Emily Clayton ◽  
Irem Sahin ◽  
Julianne Vilela ◽  
Manar E. Khalifa ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
De Novo ◽  
Tracking System ◽  
Lamp Assay ◽  
Cost Effective ◽  
Isothermal Amplification ◽  
Analytical Sensitivity ◽  
Diagnostic Device ◽  
Loop Mediated Isothermal Amplification ◽  
Resource Limited

Until vaccines and effective therapeutics become available, the practical solution to transit safely out of the current coronavirus disease 19 (CoVID-19) lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of results, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected NHS patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. Therefore, this system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.

scholarly journals Implementation of Automated Blood Culture With Quality Assurance in a Resource-Limited Setting

2021 ◽  
Vol 8 ◽  
Author(s):  
Anja von Laer ◽  
Micheline Ahou N'Guessan ◽  
Fidèle Sounan Touré ◽  
Kathrin Nowak ◽  
Karin Groeschner ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Brain Heart Infusion ◽  
Turnaround Time ◽  
Resource Limited Setting ◽  
University Hospital ◽  
Resource Limited ◽  
Skin Flora ◽  
Microbiological Laboratory ◽  
Automated Tools ◽  
Limited Setting

Background: Blood cultures (BC) have a high clinical relevance and are a priority specimen for surveillance of antimicrobial resistance. Manual BC are still most frequently used in resource-limited settings. Data on automated BC performance in Africa are scarce. We implemented automated BC at a surveillance site of the African Network for improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA).Methods: Between June 2017 and January 2018, pairs of automated BC (BacT/ALERT®FA Plus) and manual BC (brain-heart infusion broth) were compared at a University hospital in Bouaké, Côte d'Ivoire. BC were inoculated each with a target blood volume of 10 ml from the same venipuncture. Automated BC were incubated for up to 5 days, manual BC for up to 10 days. Terminal subcultures were performed for manual BC only. The two systems were compared regarding yield, contamination, and turnaround time. For quality assurance, isolates were retested in a German routine microbiological laboratory.Results: BC sampling was increased from on average 24 BC to 63 BC per month. A total of 337 matched pairs of BC were included. Automated BC was positive in 36.5%, manual BC in 24.0% (p-value &lt; 0.01), proportion of contamination was 47.9 and 43.8%, respectively (p-value = 1.0). Turnaround time of positive BC was shortened by 2.5 days with automated compared to manual BC (p &lt; 0.01). Most common detected pathogens in both systems were Klebsiella spp. (26.0%) and Staphylococcus aureus (18.2%). Most contaminants were members of the skin flora. Retesting of 162 isolates was concordant in 79.6% on family level.Conclusions: Implementing automated BC in a resource-limited setting is possible and improves microbiological diagnostic performance. Automated BC increased yield and shortened turnaround times. Regular training and mentorship of clinicians has to be intensified to increase number and quality of BC. Pre-analytical training to improve diagnostic stewardship is essential when implementing a new microbiological method. Retesting highlighted that manual identification and antimicrobial susceptibility testing can be of good quality and sustainable. The implementation of automated tools should be decided individually according to economic considerations, number of samples, stable supply chain of consumables, and technical sustainability.

scholarly journals Evaluation of sample collection and transport strategies to enhance yield, accessibility, and biosafety of COVID-19 RT-PCR testing

2021 ◽  
Author(s):  
Padmapriya Banada ◽  
David Elson ◽  
Naranjargal Daivaa ◽  
Claire Park ◽  
Samuel Desind ◽  
...  
Keyword(s):  
Sampling Methods ◽  
Diagnostic Yield ◽  
Sampling Strategy ◽  
Sample Collection ◽  
Rt Pcr ◽  
Viral Inactivation ◽  
Viral Transport ◽  
Nasal Swabs ◽  
Polymerase Chain ◽  
Transport Buffer

ABSTRACTSensitive, accessible, and biosafe sampling methods for COVID-19 reverse-transcriptase polymerase chain reaction (RT-PCR) assays are needed for frequent and widespread testing. We systematically evaluated diagnostic yield across different sample collection and transport workflows, including the incorporation of a viral inactivation buffer. We prospectively collected nasal swabs, oral swabs, and saliva, from 52 COVID-19 RT-PCR-confirmed patients, and nasopharyngeal (NP) swabs from 37 patients. Nasal and oral swabs were placed in both viral transport media (VTM) and eNAT™, a sterilizing transport buffer, prior to testing with the Xpert Xpress SARS-CoV-2 (Xpert) test. The sensitivity of each sampling strategy was compared using a composite positive standard. Overall, swab specimens collected in eNAT showed superior sensitivity compared to swabs in VTM (70% vs 57%, P=0.0022). Direct saliva 90.5%, (95% CI: 82%, 95%), followed by NP swabs in VTM and saliva in eNAT, was significantly more sensitive than nasal swabs in VTM (50%, P<0.001) or eNAT (67.8%, P=0.0012) and oral swabs in VTM (50%, P<0.0001) or eNAT (56%, P<0.0001). Saliva and use of eNAT buffer each increased detection of SARS-CoV-2 with the Xpert test; however, no single sample matrix identified all positive cases.

scholarly journals Artificial Intelligence-Assisted Loop Mediated Isothermal Amplification (ai-LAMP) for Rapid and Reliable Detection of SARS-CoV-2

2020 ◽  
Author(s):  
Mohammed A Rohaim ◽  
Emily Clayton ◽  
Irem Sahin ◽  
Julianne Vilela ◽  
Manar E Khalifa ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
De Novo ◽  
Tracking System ◽  
Lamp Assay ◽  
Cost Effective ◽  
Isothermal Amplification ◽  
Analytical Sensitivity ◽  
Diagnostic Device ◽  
Loop Mediated Isothermal Amplification ◽  
Resource Limited

Until vaccines and effective therapeutics become available, the practical way to transit safely out of the current lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of result, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms, and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. The system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.

scholarly journals COVID-19 Infection Diagnosis: Potential Impact of Isothermal Amplification Technology to Reduce Community Transmission of SARS-CoV-2

Diagnostics ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 399 ◽  
Author(s):  
Ameh James ◽  
John Alawneh
Keyword(s):  
Cost Effective ◽  
Turnaround Time ◽  
Isothermal Amplification ◽  
Resource Limited Settings ◽  
Laboratory Staff ◽  
Resource Limited ◽  
Community Transmission ◽  
Rapid Tests ◽  
Novel Coronavirus ◽  
Nicking Enzyme

The current coronavirus disease 2019 (COVID-19) pandemic is largely driven by community transmission, after 2019 novel Coronavirus (2019-nCoV or SARS-CoV-2) crosses the borders. To stop the spread, rapid testing is required at community clinics and hospitals. These rapid tests should be comparable with the standard PCR technology. Isothermal amplification technology provides an excellent alternative that is highly amenable to resource limited settings, where expertise and infrastructure to support PCR are not available. In this review, we provide a brief description of isothermal amplification technology, its potential and the gaps that need to be considered for SARS-CoV-2 detection. Among this emerging technology, loop-mediated amplification (LAMP), recombinase polymerase amplification (RPA) and Nicking enzyme-assisted reaction (NEAR) technologies have been identified as potential platforms that could be implemented at community level, without samples referral to a centralized laboratory and prolonged turnaround time associated with the standard COVID-19 RT-PCR test. LAMP, for example, has recently been shown to be comparable with PCR and could be performed in less than 30 min by non-laboratory staff, without RNA extractions commonly associated with PCR. Interestingly, NEAR (ID NOW™ COVID-19 (Abbott, IL, USA) was able to detect the virus in 5 min. More so, isothermal platforms are cost effective and could easily be scaled up to resource limited settings. Diagnostics developers, scientific community and commercial companies could consider this alternative method to help stop the spread of COVID-19.

Sign in / Sign up

Export Citation Format

Share Document