scholarly journals Limitations of PCR detection of filarial DNA in human stools from subjects non-infected with soil-transmitted helminths

Parasite ◽  
2021 ◽  
Vol 28 ◽  
pp. 47
Author(s):  
Maxime P. M. Doret ◽  
Hugues C. Nana-Djeunga ◽  
Narcisse Nzune-Toche ◽  
Sébastien D. S. Pion ◽  
Cédric B. Chesnais ◽  
...  
Keyword(s):  
Central Africa ◽  
Soil Transmitted Helminths ◽  
Non Invasive ◽  
Blood Smears ◽  
Mansonella Perstans ◽  
Stool Samples ◽  
Skin Biopsies ◽  
Low Levels ◽  
Diagnosis Technique ◽  
Standard Techniques

The standard techniques for diagnosis of human filariasis are the microscopic examination of blood smears or skin biopsies, which are relatively invasive and poorly sensitive at low levels of infection. Recently, filarial DNA has been detected in fecal samples from non-human primates in Central Africa. The aim of this study was to demonstrate proof-of-concept of a non-invasive molecular diagnosis technique for human filariasis by targeting fragments of 12S rDNA, Cox1, ITS1 and LL20-15kDa ladder antigen-gene by conventional PCR in DNA extracted from stool samples of 52 people infected with Mansonella perstans and/or Loa loa. Of these, 10 patients were infected with soil-transmitted helminths (Trichuris trichiura and/or Ascaris lumbricoides), and none were positive for Necator americanus. Interestingly, no filarial gene fragments were detected in the stools of any of the 52 patients. Future studies should evaluate whether a co-infection with soil-transmitted helminths causing gastrointestinal bleeding and likely allowing (micro)filaria exit into the digestive tract, may facilitate the molecular detection of filarial DNA fragments in stool samples.

Current status of soil-transmitted helminthiases among pre-school and school-aged children from Ile-Ife, Osun State, Nigeria

2010 ◽  
Vol 85 (3) ◽  
pp. 234-238 ◽  
Author(s):  
O.A. Sowemimo ◽  
S.O. Asaolu
Keyword(s):  
Private Schools ◽  
Private School ◽  
Primary Schools ◽  
Current Status ◽  
Parasitic Infections ◽  
Government Schools ◽  
Government School ◽  
Soil Transmitted Helminths ◽  
School Aged Children ◽  
Stool Samples

AbstractA cross-sectional survey was conducted to determine the prevalence and intensity of soil-transmitted helminths among pre-school and school-aged children attending nursery and primary schools in Ile-Ife. Single stool samples were collected between January and March, 2009 from 352 children randomly selected from a total of 456 children attending both private and government schools. The stool samples were processed using the modified Kato–Katz technique, and then examined for the eggs of soil-transmitted helminths (STHs). One hundred and twenty-one (34.4%) samples were positive for STH eggs. The overall prevalences of Ascaris lumbricoides, Trichuris trichiura and hookworm were 33.2%, 3.7% and 0.9%, respectively. The prevalence of STH infection in government schools (47.8%) was significantly higher than in private schools (16.1%) (P < 0.001). The most common type of mixed infection was the combination of A. lumbricoides and T. trichiura (6.8%). The prevalence and intensity of A. lumbricoides rose with age. The lowest prevalence and intensity (7.7%; 0.240 ± 0.136 eggs per gram (epg)) were recorded in the 2- to 3-year-old age group, while the highest prevalence and intensity (58.7%; 1.820 ± 0.237 epg) were recorded in children aged 10 years and above. A questionnaire survey indicated that 73% of the children attending private school had been treated with anthelminthics less than 2 months prior to the collection of stool specimens, while 43% of the children attending government school received anthelminthic treatment during the same period. The findings indicate that STH infections are endemic among schoolchildren in Ile-Ife and that the burden of parasitic infections is greater in government schools than in private schools.

scholarly journals Prevalence and Risk Factors of Infection with Soil Transmitted Helminths in Children from Bandjoun, the West Region of Cameroon

2020 ◽  
pp. 34-43
Author(s):  
Vanessa Rosine Nkouayep ◽  
Peter Nejsum ◽  
Dzune Fossouo Dirane Cleopas ◽  
Noumedem Anangmo Christelle Nadia ◽  
Atiokeng Tatang Rostand Joël ◽  
...  
Keyword(s):  
Risk Factors ◽  
Demographic Data ◽  
Public Health Problem ◽  
School Age Children ◽  
National Programme ◽  
Soil Transmitted Helminths ◽  
Ancylostoma Duodenale ◽  
Potential Risk Factors ◽  
Stool Samples ◽  
Associated Risk Factors

Background: Soil-transmitted helminths (STHs) continue to be a public health problem in developing countries. In Bandjoun, annual deworming is usually administered to school-age children through the national programme for the control of schistosomiasis and soil-transmitted helminthiasis in Cameroon. However, official data on the level of STH infections are scarce in this locality. Methods: We investigated the prevalence and associated risk factors of STHs among children in Bandjoun with the intention to help design future intervention plans. We obtained demographic data and potential risk factors through the interview of children using a structured questionnaire. Stool samples from these children were collected and examined for helminth eggs using Willis’ technique. Results: Three STHs were identified with an overall prevalence of 8.7%. These nematodes were Ascaris lumbricoides (8.3%), Trichuris trichiura (0.3%) and hookworms (Ancylostoma duodenale, Necator americanus) (0.7%). Failure to wash hands before meals (AOR: 2.152 [1.056-4.389]) was the main predictor associated with Ascaris infections. Not eating food picked up from the ground (AOR: 0.494 [0.261-0.937]) and not raising pigs at home (AOR: 0.109 [0.045-0.268]) reduced risk of infection. Conclusion: We recommend that STHs control interventions in Bandjoun focus on the good management of domesticated pigs, the avoidance of contact with soil and handwashing from the earliest ages as a part of daily hygiene practice.

scholarly journals Soil Transmitted Helminths and Plasmodium falciparum Co-infections among School Children in Bugesera District, Rwanda: Implications for National Control Programs

2021 ◽  
pp. 30-36
Author(s):  
Umwanankundi Marcelline ◽  
Mazigo D. Humphrey ◽  
Tumusiime David ◽  
Mucumbitsi Joseph ◽  
Arpita Sharma ◽  
...  
Keyword(s):  
School Children ◽  
Primary Schools ◽  
Spatial Scales ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Soil Transmitted Helminths ◽  
Control Programs ◽  
Stool Samples ◽  
The Impact ◽  
National Control

Soil Transmitted Helminths and Plasmodium infections are ubiquitous with morbidity and mortality within the tropical and subtropical regions. However, the extent and consequences of STH-Plasmodium co-infection at different spatial scales are poorly understood. This study aimed at determining the prevalence of Soil Transmitted Helminths and Plasmodium coinfection, and, the impact thereof among school children in Bugesera District of Eastern Rwanda. Study Design: Cross Sectional Survey Place and Duration of Study: The survey was conducted in Bugesera district, Eastern Rwanda, between May and December 2020. Methodology: The survey was conducted among children between ages 5 and 18 years, across 21 randomly selected primary schools. Stool samples were collected and screened for soil transmitted helminths using Kato-Katz, while finger-prick blood samples were examined under the microscope to determine Plasmodium infection. Results: Overall the prevalence of A. lumbricoides, T. trichiura, Hookworm and P. falciparum was 4.43%, 0.76%, 0.16% and 3.15% respectively. On the other hand, 36.15% were co-infected with A. lumbricoides and P. falciparum. Surprisingly, the coinfection was higher 41.79%, (P<0.001) in girls than the overall coinfection prevalence. Conclusion: Helminthiasis and malaria remain dominant, in spite of the continuing and tremendous national control programs. The strikingly surprising higher prevalence of A. lumbricoides-P. falciparum co-infection in girls calls for additional investigations.

scholarly journals Diagnosis of experimental stetohepatosis using ultrasound shear wave elastography

2015 ◽  
Vol 26 (1) ◽  
pp. 109-113
Keyword(s):  
Insulin Resistance ◽  
Shear Wave ◽  
Shear Wave Elastography ◽  
Mixed Diet ◽  
Sweetened Condensed Milk ◽  
Non Invasive ◽  
Condensed Milk ◽  
First Time ◽  
Diagnosis Technique

According to available literature data, NAFLD may play crucial role in the pathogenesis of type 2 diabetes and other conditions connected with insulin resistance. In order to study the essence of the NAFLD, we have created an experimental model of the steatohepatosis. The mixed diet for 8 weeks consisting of standard food (47%), sweetened condensed milk (44%), vegetable oil (8%) and vegetable starch (1%) develops non-alcoholic steatohepatosis in the animals undergoing the experiment. The morphological signs of the non-alcoholic steatohepatosis comprised as follows in the hepatocytes of the rats undergoing the experiment: presence of fine-drop fattiness (fine-drop steatosis) and accumulation of fat vacuoles shifting the nucleus towards the cell peripheral. Substantial increase in the liver pulp of the animals undergoing the experiment defined using the ultrasound shear wave elastography technique is indicative of the presence of the non-alcoholic steatohepatosis. The ultrasound shear wave elastography technique can be used as a non-invasive diagnosis marker of the non-alcoholic steatohepatosis. The said diagnosis technique has been recommended for the first time.

Loiasis in an Expatriate American Child: Diagnostic and Treatment Difficulties

PEDIATRICS ◽  
1987 ◽  
Vol 80 (6) ◽  
pp. 943-946
Author(s):  
KAREN OLNESS ◽  
RALPH A. FRANCIOSI ◽  
MARGARET M. JOHNSON ◽  
DAVID O. FREEDMAN
Keyword(s):  
Iliac Crest ◽  
Central Africa ◽  
Microtiter Plate ◽  
West African ◽  
Diagnostic Methods ◽  
Filarial Infection ◽  
Concentration Technique ◽  
Blood Smears ◽  
Blood Specimens ◽  
Skin Snips

On the basis of this experience, we recommend the following when faced with possible filariasis in an expatriate from Western Central Africa: (1) Attempt a clinical differentiation between L loa and other filarial infections present in West Africa. It is important to suspect loiasis because this is the only filarial infection that is readily curable; (2) ophthalmologic assessment to diagnose onchocerciasis; (3) if L loa is suspected, thick blood smears should be obtained from midmorning to midafternoon and stained with Giemsa or hematoxylin stains, after a concentration technique is used. Nighttime blood specimens should be obtained if the patient has been in an area where W. bancrofti is prevalent; (4) skin snip biopsies prepared as follows: Bilateral symmetrical skin snips should be taken. In the case of suspected West African filariasis, the pelvic girdle, iliac crest, and back of scapula are thought to have the highest yield. One snip from each of six different sites should be obtained. Each skin snip should be approximately 2 to 3 mm (a cornealoscleral biopsy forceps can be used). Each skin snip is placed in 100 µL (approximately one drop) of normal saline in a flat-bottomed microtiter plate. The plate is incubated at room temperature and checked periodically for 24 hours under a dissecting microscope (x20 to x40). If present, the small worms will be seen wiggling and squirming in the drop of saline; (5) serologic diagnostic methods are most efficient if human filarial antigens are used; (6) if treatment is with diethylcarbamazine, the initial dose should be small. During treatment with diethylcarbamazine, WBCs, differentials, and renal function must be monitored.

scholarly journals Development of Conventional Multiplex PCR: A Rapid Technique for Simultaneous Detection of Soil-Transmitted Helminths

Pathogens ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 152 ◽  
Author(s):  
Vivornpun Sanprasert ◽  
Ruthairat Kerdkaew ◽  
Siriporn Srirungruang ◽  
Sarit Charuchaibovorn ◽  
Kobpat Phadungsaksawasdi ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Real Time ◽  
Real Time Pcr ◽  
Intestinal Parasites ◽  
Simultaneous Detection ◽  
Diagnostic Tools ◽  
Multiple Infections ◽  
Parasitic Infections ◽  
Soil Transmitted Helminths ◽  
Stool Samples

Soil-transmitted helminths (STHs) are the most common intestinal parasites infecting humans worldwide. STH infections are a major cause of morbidity and disability. Accurate diagnostic tools are pivotal for assessing the exact prevalence of parasitic infections. Microscopic examination and culture techniques have been used to observe the presence of eggs or larvae of parasites in stool samples, but they are time-consuming and have low sensitivity. Therefore, accurate, simple, and inexpensive diagnostic techniques are still required for simultaneous detection of STH infections. Although molecular-based techniques, such as real-time PCR and multiplex real-time PCR, have been developed, they are not suitable for routine diagnosis due to the requirement for expensive reagents and instruments. In this study, we established a conventional multiplex PCR for simultaneous rapid detection of Ascaris lumbricoides, Necator americanus, and Strongyloides stercoralis in stool samples. Our results show that the multiplex PCR could detect the DNA of STHs at a very low target gene concentrations (lower than 1 pg) with no cross-amplification. Multiplex PCR had five times higher sensitivity than the formalin–ethyl acetate concentration technique (FECT) in the detection of multiple infections, and two times higher for detection of S. stercoralis. However, multiplex PCR was comparable to FECT in the detection of A. lumbricoides and N. americanus. In conclusion, this method could be used as an alternative method for the detection of STHs, especially for S. stercoralis.

scholarly journals P835 Correlation between microbial markers and faecal calprotectin in IBD patients

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S648-S648
Author(s):  
J Amoedo Cibeira ◽  
S Ramió-Pujol ◽  
M Serra-Pagès ◽  
A Bahí ◽  
C Puig-Amiel ◽  
...  
Keyword(s):  
Disease Activity ◽  
Negative Correlation ◽  
Inflammatory Disease ◽  
Standard Technique ◽  
Significant Negative Correlation ◽  
Intestinal Lesion ◽  
Faecal Calprotectin ◽  
Non Invasive ◽  
Stool Samples ◽  
Active Inflammation

Abstract Background Crohn disease (CD) and Ulcerative colitis (UC) are characterised by episodes of exacerbations and remissions. Monitoring disease activity based on intestinal lesion is mandatory prior to any change in the therapeutic strategy. Colonoscopy is the gold standard technique to monitor the disease activity in IBD patients, but it is usually discarded because of costs and risk issues. The concentration of Faecal Calprotectin (FC) is widely used as a non-invasive marker of inflammation of the intestinal mucosa, allowing the assessment of the disease activity. Recently, different studies have demonstrated that certain microbial species, part of intestinal microbiota which can be detected in stool samples, are capable of correlating with disease activity in CD and UC patients. The purpose of this study was to analyse the correlation between these microbial indicators and the FC to monitor the disease activity in CD and UC patients. Methods FC levels were used to define inflammatory disease activity, the predetermined cut-off of 250 μg/g of faeces was used, higher values indicated an active inflammation and lower values indicated disease in remission. Two cohorts consisting of 61 patients of CD (25 with active inflammation and 36 with remission) and 90 of UC (42 with active inflammation and 48 with remission) were recruited by the Gastroenterology department of 4 Catalan hospitals. A sample of faeces was collected from each patient. FC and the following markers were quantified by qPCR: Faecalibacterium prausnitzii (Fpra), Escherichia coli (Eco), Akkermansia muciniphila (Akk), Ruminococcus sp. (Rum), Bacteroidetes (Bac) and Methanobrevibacter smithii (Msm) for each sample. Results The bacterial markers presented different behaviour depending on the disease analysed. The abundances of Eco and Bac were higher in CD with active inflammation compared with CD with remission. In contrast, no significant differences were found for Fpra, Akk, Rum, and Msm. Besides, a significant positive correlation between Eco abundance and FC levels (0.280, p = 0.029) and a significant negative correlation between Msm and FC levels (−0.299, p = 0.021) were observed. According UC patients, while the abundance of Eco was higher in patients with active inflammation, the abundance of Rum was significantly less abundant. No significant differences were found for Fpra, Akk, Bac, and Msm. Moreover, we also observed a significant negative correlation between Rum and FC levels (−0.308, p = 0.003, respectively). Conclusion The abundance of Eco and Msm in CD patients and the abundance of Rum in UC patients correlate to FC in order to determine inflammatory disease activity. So, these markers can also be an accurate discriminator of active disease in CD and UC patients.

scholarly journals Identification of a native novel oncolytic immunoglobulin on exfoliated colon epithelial cells: A bispecific heterodimeric chimera of IgA/IgG

2017 ◽  
Author(s):  
George P. Albaugh ◽  
Sudhir K. Dutta ◽  
Vasantha Iyengar ◽  
Samina Shami ◽  
Althaf Lohani ◽  
...  
Keyword(s):  
Stem Cell ◽  
Direct Method ◽  
Stem Cell Markers ◽  
Distinct Cell ◽  
Stem Cell Medium ◽  
Stool Samples ◽  
Low Levels ◽  
Colonic Cells ◽  
Cell Medium ◽  
A Direct Method

ABSTRACTUnderstanding the nature of cell surface markers on exfoliated colonic cells is a crucial step in establishing criteria for a normally functioning mucosa. We have found that colonic cells isolated from stool samples (SCSR-010 Fecal Cell Isolation Kit, NonInvasive Technologies, Elkridge, MD), preserved at room temperature for up to one week, with viability of >85% and low levels of apoptosis (8% - 10%) exhibit two distinct cell size subpopulations, in the 2.5μM– 5.0 μM and 5.0μM-8.0μM range. In addition to IgA, about 60% of the cells expressed a novel heterodimeric IgA/IgG immunoglobulin that conferred a broad-spectrum cell mediated cytotoxicity against tumor cells. In a cohort of 58 subjects the exclusive absence of this immunoglobulin in two African-Americans was suggestive of a germline deletion. Serial cultures in stem cell medium retained the expression of this heterodimer. Since a majority of the cystic cells expressed the stem cell markers Lgr5 and Musashi-1 we termed these cells as gastrointestinal progenitor stem cells (GIP-C**). CXCR-4, the cytokine co-receptor for HIV was markedly expressed. These cells also expressed CD20, IgA, IgG, CD45, and COX-2. We assume that they originated from mature columnar epithelium by dedifferentiation. Our observations indicate that we have a robust noninvasive method to study mucosal pathophysiology and a direct method to create a database for applications in regenerative medicine.

scholarly journals Confirmation of multi-parallel quantitative real-time PCR as the gold standard for detecting soil-transmitted helminths in stool

2021 ◽  
Author(s):  
Marina Papaiakovou ◽  
Nils Pilotte ◽  
Julia Dunn ◽  
David TJ Littlewood ◽  
Rubén O Cimino ◽  
...  
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Gold Standard ◽  
Low Cost ◽  
Strongyloides Stercoralis ◽  
Diagnostic Methods ◽  
Quantitative Real Time Pcr ◽  
Soil Transmitted Helminths ◽  
Stool Samples ◽  
Kappa Agreement

AbstractDue to its simplicity and cost-effectiveness, microscopy has seen extensive field-use as the diagnostic standard for the detection of soil-transmitted helminths (STH) in stool samples. However, the sensitivity of microscopy-based detection is inadequate in reduced-transmission settings where worm burden is oftentimes low. Equally problematic, eggs of closely related species oftentimes have indistinguishable morphologies, leading to species misidentification. In light of these shortcomings, the purpose of this study was to demonstrate multi-parallel quantitative real-time PCR (qPCR) as the new “gold standard” for STH detection. Accordingly, stool samples from non-endemic participants were spiked with limited numbers of eggs or larvae (1 to 40) of five different species of STH. DNA extracts were tested using two unique multi-parallel real-time PCR-based diagnostic methods. These methods employed different target sequences (ribosomal internal transcribed spacer, or highly repetitive non-coding regions), to evaluate the detection of DNA from as little as one egg per sample. There was a statistically significant kendall correlation between egg/larvae counts and qPCR from both methods for Trichuris trichiura (0.86 and 0.872 for NHM and Baylor assays) and a strong correlation (0.602 and 0.631 for NHM and Baylor assays, respectively) for Ascaris lumbricoides. Less strong but still significant was the Kendall Tau-b value for A. duodenale (0.408 for both) and for S. stercoralis (0.483 and 0.653, respectively). In addition, using field stool samples from rural Argentina both assays had fair to moderate kappa agreement (0.329-0.454), except for Strongyloides stercoralis (0.121) that both assays had slight agreement. In spite of the small cohort of samples, both qPCR assays, targeting of two independent genomic regions, provided reproducible results and we believe that, low cost multi-parallel quantitative real-time PCR-based diagnostics should supplant microscopy as the new gold standard for stool-based detection of soil transmitted helminths in public-health and community settings.

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