We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App




Events

09 Apr 2024 - 12 Apr 2024
15 Apr 2024 - 17 Apr 2024
23 Apr 2024 - 26 Apr 2024

LAMP Assay Developed for Threadworms in Stool and Urine

By LabMedica International staff writers
Posted on 26 Jul 2016
Print article
Image: A photomicrograph of an adult free-living female S. stercoralis alongside a smaller rhabditiform larva. Notice the developing eggs in the adult female (Photo courtesy of the CDC).
Image: A photomicrograph of an adult free-living female S. stercoralis alongside a smaller rhabditiform larva. Notice the developing eggs in the adult female (Photo courtesy of the CDC).
Strongyloides stercoralis, commonly known as threadworm, is a nematode globally distributed but mainly endemic in tropical and subtropical regions and is the chief causative agent of human strongyloidiasis.

The diagnosis of strongyloidiasis is suspected when clinical signs and symptoms, eosinophilia or serologic findings are observed, but definitive diagnosis is accomplished by parasitological examination of stool samples allowing the morphological identification of S. stercoralis, including direct smear in saline, the spontaneous sedimentation method, and centrifugation.

Scientists at the University of Salamanca (Salamanca, Spain) and their colleagues developed, a molecular assay using loop mediated isothermal amplification (LAMP) methodology as a simple, sensible and robust method for the detection of S. venezuelensis DNA in a well-established rodent model infection in both stool and urine samples. The LAMP assay was also successfully evaluated in patients´ stool samples. The LAMP assay (Strong-LAMP) is a useful molecular tool in a strongyloidiasis infection model and could be a potential field-friendly diagnostic test in a clinical setting, following further validation.

Stool samples were collected from 12 patients who showed significant levels of immunoglobulin E (IgE), eosinophilia or other symptoms suggestive of disease. Stool samples were examined after arrival by qualified laboratory technicians. Eleven of these 12 stool samples were subjected to different parasitological methods as screening tests for strongyloidiasis, including microscopic examination (MOE) for the presence of rabditiform larvae in direct fecal smears, agar plate culture (APC) or Harada-Mori´s filter paper culture method (HMM).

DNA was extracted from the human stool samples and tested by an optimized real-time polymerase chain reaction. To evaluate the ability of the LAMP assay designed to amplify S. venezuelensis DNA in real samples, the team used DNA extracted from the pooled feces and urine samples taken daily from each experimentally infected group of rats with different doses. To check whether LAMP assay designed was also able to amplify DNA from S. stercoralis in clinical samples, they used the patients´ stool samples included in the study.

All patients´ stool samples were tested by RT-PCR and LAMP to compare results. The RT-PCR resulted positive in 6/7 patients´ stool samples with confirmed strongyloidiasis by parasitological tests previously applied. In addition, a positive result was obtained in a sample to which no parasitological test could be performed; negative results were obtained in negative parasitological samples for S. stercoralis. All patients´ stool samples with confirmed strongyloidiasis by parasitological tests could be detected by LAMP, including the sample, which resulted negative in previous RT-PCR analyses.

The authors concluded that the Strong-LAMP assay can be applied effectively for the detection of S. stercoralis DNA in patients´ stool samples. The successfully amplification of Strongyloides spp. DNA in infected urine samples by LAMP assay as well as the advantages that urine would have in collection, storage and processing in comparison to patients´ stool samples, should make us consider the possibility of starting to use urine specimens in diagnosing human strongyloidiasis. The study was published on July 14, 2016, in the journal Public Library of Science Neglected Tropical Diseases.

Related Links:
University of Salamanca


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
One Step HbA1c Measuring System
GREENCARE A1c
Anti-Cyclic Citrullinated Peptide Test
GPP-100 Anti-CCP Kit
Gold Member
Xylazine Immunoassay Test
Xylazine ELISA

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: MOF materials efficiently enrich cfDNA and cfRNA in blood through simple operational process (Photo courtesy of Science China Press)

Blood Circulating Nucleic Acid Enrichment Technique Enables Non-Invasive Liver Cancer Diagnosis

The ability to diagnose diseases early can significantly enhance the effectiveness of clinical treatments and improve survival rates. One promising approach for non-invasive early diagnosis is the use... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The OvaCis Rapid Test discriminates benign from malignant epithelial ovarian cysts (Photo courtesy of INEX)

Intra-Operative POC Device Distinguishes Between Benign and Malignant Ovarian Cysts within 15 Minutes

Ovarian cysts represent a significant health issue for women globally, with up to 10% experiencing this condition at some point in their lives. These cysts form when fluid collects within a thin membrane... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.