scholarly journals Identifi cation of Plasmodium species from outdated blood samples by nested-PCR compared with microscopy diagnosis in Jazan region, Saudi Arabia

2017 ◽  
Vol 10 (2) ◽  
pp. 68-75 ◽  
Author(s):  
O. M. Dafalla ◽  
A. A. Alsheikh ◽  
Abakar A. D. ◽  
W. S. Mohammed ◽  
Bakri Y. M. Nour ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Nested Pcr ◽  
Plasmodium Species ◽  
Blood Samples

scholarly journals Determining the Potential Value of Salivary Plasmodium Falciparum Hisditine-Rich Protein 2 and Lactate Dehydrogenase as a Non-Invasive Test for Malaria

2020 ◽  
Author(s):  
FRANCIS OPOKU AGYAPONG ◽  
Daniel Ansong ◽  
Alex Owusu-Ofori ◽  
Ruby Martin-Peprah ◽  
Millicent Opoku ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Lactate Dehydrogenase ◽  
Nested Pcr ◽  
Plasmodium Species ◽  
Laboratory Diagnosis ◽  
Malaria Prevalence ◽  
Blood Film ◽  
Sub Saharan Africa ◽  
Alternative Methods ◽  
Blood Samples

Abstract Background Malaria remains an important public health threat claiming many lives particularly in Sub-Saharan Africa. Light microscopy which is a blood-based test is the Gold standard for laboratory diagnosis of malaria in the clinical settings. The lack of sensitivity of Microscopy coupled with the challenges associated with blood sampling necessitates exploring alternative methods of identifying malaria cases. Aims and Objectives The aim of this study was to detect the presence of Plasmodium Lactate Dehydrogenase (pLDH) and Plasmodium falciparum Histidine-Rich Protein 2 (PfHRP2) in the saliva of suspected malaria patients and to compare the diagnostic accuracy of these saliva-borne biomarkers with the results of blood film microscopy using Nested PCR as the reference test. Methods The research was a comparative study. Matched saliva and blood samples of suspected malaria patients were collected. The blood samples were aliquoted into 2 smaller volumes and used to run blood film microscopy (thick and thin) and Nested PCR to detect DNA of the 5 Plasmodium species known to clinically infect man. Sand-wiched ELISA was separately run to qualitatively detect pLDH and PfHRP2 in the saliva samples. Accuracy indices of the saliva-based assays (saliva pLDH and PfHRP2) were compared with the conventional blood-based Microscopy. Results Of the participating 188 subjects, malaria prevalence rates of 51 (27.13%), 80(42.55%), 117 (62.23%) and 95 (50.53%) were detected by the Microscopy, saliva pLDH, saliva PfHRP2 and the PCR respectively. The sensitivity of the saliva PfHRP2 ELISA, 78.95% (95% CI, 69.38-86.64%) and saliva pLDH ELISA, 64.21% (95% CI 53.72 -73.79) were better than those obtained for the blood film Microscopy. Conclusions The saliva pLDH and the PfHRP2 ELISAs were found to be more sensitive (64.21% and 78.95% respectively) in defining malaria cases than the results obtained for the conventional blood film microscopy. Both the saliva pLDH and the PfHRP2 ELISAs showed moderate agreement with the results of the Nested PCR with Kappa co-efficient of 0.44 and 0.5 respectively.

scholarly journals Molecular characteristics of HBV infection among blood donors tested HBsAg reactive in a single ELISA test in southern China

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xianlin Ye ◽  
Tong Li ◽  
Ran Li ◽  
Heng Liu ◽  
Junpeng Zhao ◽  
...  
Keyword(s):  
Viral Load ◽  
Hepatitis B ◽  
Nested Pcr ◽  
Blood Donors ◽  
Southern China ◽  
Core Promoter ◽  
Elisa Test ◽  
Hbv Infection ◽  
Molecular Characteristics ◽  
Blood Samples

Abstract Background Hepatitis B virus (HBV) infection is a major concern for blood safety in high-prevalence HBV countries such as China. In Shenzhen, dual hepatitis B surface antigen (HBsAg) enzyme-linked immunosorbent assays (ELISAs) have been adopted in parallel with nucleic acid testing (NAT) for donors for over a decade. A small proportion of blood donors test reactive (R) for HBsAg but negative through routine NAT, which can lead to HBV infection with an extremely low viral load. Objectives We aimed to investigate and analyze the molecular characteristics of HBV among blood donors that tested HBsAg R in a single ELISA test. Methods Blood donations were evaluated in this study if confirmed HBsAg R through one of two ELISA kits. Samples with non-reactive (NR) results by NAT were collected and tested for HBsAg by chemiluminescent microparticle immunoassay (CLIA) with a neutralization test. The level of HBsAg was further assessed by electrochemiluminescence immunoassay (ECLIA). The viral basic core promoter (BCP) and pre-core (PC) and S regions were amplified by nested PCR. Quantitative real-time PCR (qPCR) for viral load determination and individual donation (ID)-NAT were adopted simultaneously. HBsAg was confirmed with CLIA, ECLIA, nested PCR, qPCR, and ID-NAT. Results Of the 100,252 donations, 38 and 41 were identified as HBsAg R with Wantai and DiaSorin ELISA kits, respectively. Seventy-nine (0.077%, 79/100,252) blood samples with ELISA R-NR and NAT NR results were enrolled in the study. Of these, 17 (21.5%,17/79) were confirmed as HBsAg-positive. Of the 14 genotyped cases, 78.6% (11/14) were genotype B, and C and D were observed in two and one sample, respectively. Mutations were found in the S gene, including Y100C, Y103I, G145R, and L175S, which can affect the detection of HBsAg. A high-frequency mutation, T1719G (93.3%), was detected in the BCP/PC region, which reduced the viral replication. Conclusion A small number of blood samples with HBsAg ELISA R-NR and NAT NR results were confirmed as HBV infection, viral nucleic acids were found in most of the samples through routine NAT methods. It is necessary to employ more sensitive and specific assays for the detection of HBV infection among blood donors.

Detection of lymphatic Wuchereria bancrofti in carriers and long-term storage blood samples using semi-nested PCR

2005 ◽  
Vol 19 (3) ◽  
pp. 169-172 ◽  
Author(s):  
P. Kanjanavas ◽  
P. Tan-ariya ◽  
P. Khawsak ◽  
A. Pakpitcharoen ◽  
S. Phantana ◽  
...  
Keyword(s):  
Nested Pcr ◽  
Wuchereria Bancrofti ◽  
Blood Samples ◽  
Long Term Storage ◽  
Term Storage

A nested PCR assay exhibits enhanced sensitivity for detection of Theileria parva infections in bovine blood samples from carrier animals

2009 ◽  
Vol 106 (2) ◽  
pp. 357-365 ◽  
Author(s):  
David O. Odongo ◽  
Jack D. Sunter ◽  
Henry K. Kiara ◽  
Robert A. Skilton ◽  
Richard P. Bishop
Keyword(s):  
Nested Pcr ◽  
Theileria Parva ◽  
Bovine Blood ◽  
Pcr Assay ◽  
Blood Samples ◽  
Enhanced Sensitivity

scholarly journals Molecular characterization of Leishmania tropica and Leishmania major from stray dogs and patients in Saudi Arabia

2020 ◽  
Author(s):  
Abdullah D Alanazi ◽  
Abdulazi S Alouffi S Alouffi ◽  
Mohamed S Alyousif S Alyousif ◽  
Abdulsadah A Rahi ◽  
Magda A Ali ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Cutaneous Leishmaniasis ◽  
Nested Pcr ◽  
Leishmania Major ◽  
Sand Fly ◽  
Human Populations ◽  
Leishmania Tropica ◽  
Stray Dogs ◽  
Wild Canids ◽  
Control And Prevention

Abstract Background: Leishmania major and Leishmania tropica cause cutaneous leishmaniasis in humans and dogs in several parts of the world, with a large number of cases recorded in the Middle East. However, when occurring in sympatry, the role of each species of Leishmania in the epidemiology of cutaneous leishmaniasis (CL) is not clear. Methods: To determine the prevalence and to identify the species of Leishmania that infects humans and stray dogs in Riyadh and Al-Qassim (Saudi Arabia), 311 stray dogs and 27 human patients, suspected for Leishmania, were examined for CL by a nested PCR (nPCR).Results: Nested PCR (nPCR) detected seven patients (25.9%) positive for cutaneous leishmaniasis. Five patients from Riyadh were infected by L. major and two from Al-Qassim by L. tropica. In addition, five dogs (1.6%) were infected by L. tropica. Conclusions: This is one of the first molecular studies of leishmaniasis from Saudi Arabia. The relationship between the sand fly vectors and the reservoirs of both Leishmania spp. is still scarcely known in this region, and further epidemiological investigations of domestic and wild canids infected with L. major and L. tropica are needed towards a control and prevention of the infection in canine and human populations.

scholarly journals Diagnostic potential of nested PCR, galactomannan EIA, and Beta-D-glucan for invasive aspergillosis in pediatric patients

2012 ◽  
Vol 6 (04) ◽  
pp. 352-357 ◽  
Author(s):  
Parisa Badiee ◽  
Abdolvahab Alborzi ◽  
Mahammad Karimi ◽  
Bahman Pourabbas ◽  
Pedram Haddadi ◽  
...  
Keyword(s):  
Invasive Aspergillosis ◽  
Nested Pcr ◽  
Pediatric Patients ◽  
Clinical Samples ◽  
Predictive Values ◽  
Blood Samples ◽  
Diagnostic Potential ◽  
Increased Risk ◽  
Galactomannan Antigen ◽  
Noninvasive Tests

Introduction: Limited specific data and investigations are available for invasive aspergillosis (IA) in pediatric patients. We evaluated the diagnostic potential of three noninvasive tests including the Platelia Aspergillus EIA kit for using galactomannan antigen, (1,3)-β-D-glucan Detection Reagent Kit, and nested-PCR for Aspergillus DNA in sera. We evaluated the diagnostic potential of three noninvasive tests including EIA for galactomannan antigen  (Platelia Aspergillus), nested  PCR assay for Aspergillus DNA and test for  (1→3)-β-D-glucan (Glucatell assay Kit). Methodology: All pediatric patients treated at the hematology/oncology unit who were at increased risk of developing invasive aspergillosis were enrolled. Clinical samples were examined for Aspergillus infections by mycological methods. Serial blood samples were collected twice weekly and evaluated by noninvasive tests. Results: We analyzed 230 consecutive blood samples from 62 pediatric patients. The incidence rate of invasive aspergillosis in the patients was found to be 27.4%, and the etiologic agents were Aspergillus flavus, Aspergillus fumigatus, and Aspergillus spp.  The sensitivity, specificity, positive and negative predictive values, and likelihood ratios for positive and negative results of galactomannan in patients with proven and probable IA were 90%, 92%, 81.8%, 96%, 11.25, and 0.1; for beta-D-glucan they were 50%, 46%, 26%, 70.6%, 0.9, 0.9; and for nested-PCR they were 80%, 96.2%, 88.9%, 92.6%, 21, and 0.2, respectively. Conclusions: The conventional methods are not able to detect IA, due to the lack of valid and proper sampling. Galactomannan and nested-PCR tests in serum, with enough accuracy and reliability, can serve as noninvasive methods for the detection of IA in pediatric patients. However, the beta-D-glucan test cannot serve as an efficient diagnostic tool in those with hematologic disorders. 

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