Identification of Leishmania infantum in blood donors from endemic regions for visceral leishmaniasis

Parasitology ◽  
2020 ◽  
pp. 1-5
Author(s):  
Loren Queli Pereira ◽  
Márcia Maria Ferreira-Silva ◽  
Cristhianne Molinero Andrade Ratkevicius ◽  
César Gómez-Hérnandez ◽  
Fernanda Bernadelli De Vito ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Blood Donors ◽  
Asymptomatic Infection ◽  
Molecular Techniques ◽  
Enzyme Linked Immunosorbent Assay ◽  
Conventional Pcr ◽  
Asymptomatic Patients ◽  
Polymerase Chain ◽  
Asymptomatic Individuals

Abstract Visceral leishmaniasis is an endemic protozoonosis observed in over 60 countries, with over 500 000 new cases recorded annually. Although the diagnostic procedure of its symptomatic forms is well established, for asymptomatic patients, who represent about 85% of those infected, there is no consensus on the best method for its identification. Recent studies have presented molecular techniques as viable identification methods, with good sensitivity and specificity indices in asymptomatic individuals. Therefore, we aimed to use molecular methods to assess their effectiveness in identifying the presence of asymptomatic infection by Leishmania infantum (L. infantum) individuals from endemic regions of Brazil. Screening was performed by real-time polymerase chain reaction (qPCR) and confirmed by sequencing the cytochrome B gene. Of the 127 samples [from 608 blood donors who had participated in a previous study, of which 34 were positive by the enzyme-linked immunosorbent assay (ELISA) rK39] tested by qPCR, 31 (24.4%) were positive. In the sequencing of 10 qPCR-positive samples, five were identified as L. infantum. Complimentary samples of the ELISA rK39 and conventional PCR showed only reasonable and low agreement with qPCR, respectively. The qPCR confirmed the presence of infection in five of the 10 sequenced samples, ELISA confirmed three, and the conventional PCR confirmed none.

scholarly journals Development and Validation of a PCR-ELISA for the Diagnosis of Symptomatic and Asymptomatic Infection byLeishmania (Leishmania) infantum

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Fernanda Alvarenga Cardoso Medeiros ◽  
Luciana Inácia Gomes ◽  
Edward Oliveira ◽  
Carolina Senra Alves de Souza ◽  
Maria Vitória Mourão ◽  
...  
Keyword(s):  
Detection Limit ◽  
Peripheral Blood ◽  
Leishmania Infantum ◽  
Asymptomatic Infection ◽  
Enzyme Linked Immunosorbent Assay ◽  
Healthy Individuals ◽  
Blood Samples ◽  
Hiv Coinfection ◽  
Satisfactory Precision ◽  
Asymptomatic Individuals

AkDNAPCR enzyme-linked immunosorbent assay (kDNAPCR-ELISA) for the diagnosis of human visceral leishmaniasis (HVL) was developed. The detection limit of the reaction, precision measurements, and cut-off of thekDNAPCR-ELISA were defined in a proof-of-concept phase. A reference strain ofLeishmania (Leishmania) infantumand a bank of 14 peripheral blood samples from immunocompetent patients with VL were characterized using techniques considered gold standards, and 11 blood samples obtained from healthy individuals of an endemic area were also assessed. Phase II evaluation determined the performance of the assay in peripheral blood samples from 105 patients with VL (adults and children), 25 patients withLeishmania/HIV coinfection, 40 healthy individuals, and 33 asymptomatic individuals living in endemic areas. ThekDNAPCR-ELISA exhibited satisfactory precision, with a detection limit of 0.07 fg of DNA fromL.(L.) infantumand 1 parasite/mL blood. The overall sensitivity of the assay for all groups studied was 100% (95% confidence interval [CI]: 97.1–100%), and the specificity was 95% (95% CI: 83.5–98.6%). ThekDNAPCR-ELISA was shown to be a useful tool for VL symptomatic and asymptomatic individuals diagnosis and its use in endemic countries may help monitor control interventions.

Evaluation of molecular techniques to visceral leishmaniasis detection in asymptomatic patients: a systematic review

2021 ◽  
Author(s):  
Amanda Virginia Batista Vieira ◽  
Pablo Cantalice Santos Farias ◽  
Gilberto Silva Nunes Bezerra ◽  
Amanda Tavares Xavier ◽  
Manoel Sebastião da Costa Lima Júnior ◽  
...  
Keyword(s):  
Systematic Review ◽  
Visceral Leishmaniasis ◽  
Molecular Techniques ◽  
Asymptomatic Patients

scholarly journals USE OF THE POLYMERASE CHAIN REACTION FOR THE DIAGNOSIS OF ASYMPTOMATIC Leishmania INFECTION IN A VISCERAL LEISHMANIASIS-ENDEMIC AREA

2013 ◽  
Vol 55 (2) ◽  
pp. 101-104 ◽  
Author(s):  
Luciana Almeida Silva ◽  
Héctor Dardo Romero ◽  
Aline Fagundes ◽  
Nédia Nehme ◽  
Otávio Fernandes ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Visceral Leishmaniasis ◽  
Endemic Area ◽  
Asymptomatic Infection ◽  
Control Measures ◽  
Skin Tests ◽  
Leishmania Infection ◽  
Chain Reaction ◽  
Serological Tests ◽  
Polymerase Chain

The diagnosis of asymptomatic infection with Leishmania (Leishmania) chagasi has become more important over recent years. Expansion of visceral leishmaniasis might be associated with other routes of transmission such as transfusion, congenital or even vector transmission, and subjects with asymptomatic infection are potential reservoirs. Moreover, the identification of infection may contribute to the management of patients with immunosuppressive conditions (HIV, transplants, use of immunomodulators) and to the assessment of the effectiveness of control measures. In this study, 149 subjects living in a visceral leishmaniasis endemic area were evaluated clinically and submitted to genus-specific polymerase chain reaction (PCR), serological testing, and the Montenegro skin test. Forty-nine (32.9%) of the subjects had a positive PCR result and none of them developed the disease within a follow-up period of three years. No association was observed between the results of PCR, serological and skin tests. A positive PCR result in subjects from the endemic area did not indicate a risk of progression to visceral leishmaniasis and was not associated with a positive result in the serological tests.

scholarly journals Subtractive Phage Display Selection from Canine Visceral Leishmaniasis Identifies Novel Epitopes That Mimic Leishmania infantum Antigens with Potential Serodiagnosis Applications

2013 ◽  
Vol 21 (1) ◽  
pp. 96-106 ◽  
Author(s):  
Lourena E. Costa ◽  
Mayara I. S. Lima ◽  
Miguel A. Chávez-Fumagalli ◽  
Daniel Menezes-Souza ◽  
Vivian T. Martins ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Phage Display ◽  
Leishmania Infantum ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Phage Display Technology ◽  
Predictive Values ◽  
Content Type ◽  
Phage Elisa

ABSTRACTVisceral leishmaniasis (VL) is a zoonotic disease that is endemic to Brazil, where dogs are the main domestic parasite reservoirs, and the percentages of infected dogs living in regions where canine VL (CVL) is endemic have ranged from 10% to 62%. Despite technological advances, some problems have been reported with CVL serodiagnosis. The present study describes a sequential subtractive selection through phage display technology from polyclonal antibodies of negative and positive sera that resulted in the identification of potential bacteriophage-fused peptides that were highly sensitive and specific to antibodies of CVL. A negative selection was performed in which phage clones were adhered to purified IgGs from healthy andTrypanosoma cruzi-infected dogs to eliminate cross-reactive phages. The remaining supernatant nonadhered phages were submitted to positive selection against IgG from the blood serum of dogs that were infected withLeishmania infantum. Phage clones that adhered to purified IgGs from the CVL-infected serum samples were selected. Eighteen clones were identified and their reactivities tested by a phage enzyme-linked immunosorbent assay (phage-ELISA) against the serum samples from infected dogs (n= 31) compared to those from vaccinated dogs (n= 21), experimentally infected dogs with cross-reactive parasites (n= 23), and healthy controls (n= 17). Eight clones presented sensitivity, specificity, and positive and negative predictive values of 100%, and they showed no cross-reactivity withT. cruzi- orEhrlichia canis-infected dogs or with dogs vaccinated with two different commercial CVL vaccines in Brazil. Our study identified eight mimotopes ofL. infantumantigens with 100% accuracy for CVL serodiagnosis. The use of these mimotopes by phage-ELISA proved to be an excellent assay that was reproducible, simple, fast, and inexpensive, and it can be applied in CVL-monitoring programs.

Asymptomatic human blood donors carriers of Leishmania infantum : Potential reservoirs for visceral leishmaniasis in northwestern Iran

2017 ◽  
Vol 56 (3) ◽  
pp. 474-479 ◽  
Author(s):  
Shabnam Asfaram ◽  
Mahdi Fakhar ◽  
Mehdi Mohebali ◽  
Ahmad Mardani ◽  
Elham Sadat Banimostafavi ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Human Blood ◽  
Leishmania Infantum ◽  
Blood Donors ◽  
Northwestern Iran

scholarly journals Serological and Molecular Detection of Hepatitis B virus among patients referred to Kurdistan Center for Hepatology and Gastroenterology in Sulaimani City/Kurdistan Region of Iraq

2020 ◽  
Vol 4 (2) ◽  
pp. 117
Author(s):  
Raz Sirwan Abdulla ◽  
Salih Ahmed Hama
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hbv Dna ◽  
Molecular Techniques ◽  
Enzyme Linked Immunosorbent Assay ◽  
Rt Pcr ◽  
B Virus ◽  
Polymerase Chain ◽  
Pcr Techniques ◽  
Positive Results

Hepatitis B virus infection is caused by the hepatitis B virus, a major global health problem. This infection can lead to chronic conditions, followed by cirrhosis and hepatocellular carcinoma (HCC). The current study was aimed to detect HBV using serological and molecular techniques. During 2019, 300 blood samples were collected from Kurdistan Center for Hepatology and Gastroenterology in Sulaimani city. Enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) techniques were used for the detection of HBsAg and HBV DNA, respectively. Obtained results were revealed that 92 out of 300 tested patients (30.66%) seropositive for HBsAg. Among 92 seropositive patients, 53 were shown positive results for HBV DNA by RT-PCR. Dental clinic visiting and dialysis were among the important risk factors for HBV transmission. The vast majority of positive results were among males. Smokers showed relatively high rates of positive results. One-third of the referred patients who had liver complaints were positive for HBsAg. More than half of the seropositive patients showed RT-PCR positive results. It was concluded that the molecular method (RT-PCR) is more sensitive and gives a more accurate result than serology (ELISA). Therefore, it can be used as a diagnostic tool for HBV detection.

scholarly journals Seeing beyond a Dilated Proventriculus: Diagnostic Tools for Proventricular Dilatation Disease in Psittacine Birds

Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3558
Author(s):  
Jeann Leal de Araújo ◽  
Raquel Rubia Rech
Keyword(s):  
Molecular Techniques ◽  
Diagnostic Tools ◽  
Enzyme Linked Immunosorbent Assay ◽  
Rt Pcr ◽  
Postmortem Diagnosis ◽  
Concise Review ◽  
Life Threatening ◽  
Polymerase Chain ◽  
Proventricular Dilatation Disease ◽  
Diagnostic Outcomes

Proventricular dilatation disease (PDD) is a life-threatening neurological disease caused by parrot bornaviruses (PaBVs) that affects several species worldwide. PDD can be clinically manifested as either a central nervous system condition or a gastrointestinal condition if the nerves and ganglia of the gastrointestinal tract are compromised. We intend to provide a concise review for veterinary clinicians and diagnosticians with focus on the main tools available for PDD diagnosis, including gross and histopathology, immunohistochemistry, molecular techniques and serology. We suggest that a combination of different strategies can increase the success of diagnostic outcomes, as tools such as reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) can be implemented for identification of bornaviral infections in live patients, and gross pathology, histopathology, immunohistochemistry and RT-PCR can provide reliable results for postmortem diagnosis of PDD.

scholarly journals Development of an Electrochemical Immunosensor for Specific Detection of Visceral Leishmaniasis Using Gold-Modified Screen-Printed Carbon Electrodes

Biosensors ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 81 ◽  
Author(s):  
Beatriz R. Martins ◽  
Yanne O. Barbosa ◽  
Cristhianne M. R. Andrade ◽  
Loren Q. Pereira ◽  
Guilherme F. Simão ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Electrochemical Immunosensor ◽  
False Positives ◽  
Cross Reaction ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Cross Reactions ◽  
Asymptomatic Patients ◽  
Screen Printed Carbon Electrode ◽  
Screen Printed

Visceral leishmaniasis is a reemerging neglected tropical disease with limitations for its diagnosis, including low concentration of antibodies in the serum of asymptomatic patients and cross-reactions. In this context, this work proposes an electrochemical immunosensor for the diagnosis of visceral leishmaniasis in a more sensitive way that is capable of avoiding cross-reaction with Chagas disease (CD). Crude Leishmania infantum antigens tested in the enzyme-linked immunosorbent assay (ELISA) were methodologically standardized to best engage to the sensor. The antibodies anti-Trypanosoma cruzi and anti-Leishmania sp. Present in serum from patients with diverse types of CD or leishmaniasis were chosen. A screen-printed carbon electrode modified with gold nanoparticles was the best platform to guarantee effective adsorption of all antigens so that the epitope of specific recognition for leishmaniasis occurred efficiently and without cross-reaction with the evaluated CD. The current peaks reduced linearly after the recognition, and still were able to notice the discrimination between different kinds of diseases (digestive, cardiac, undetermined Chagas/acute and visceral chronic leishmaniasis). Comparative analyses with ELISA were performed with the same groups, and a low specificity (44%) was verified due to cross-reactions (high number of false positives) on ELISA tests, while the proposed immunosensor presented high selectivity and specificity (100%) without any false positives or false negatives for the serum samples from isolated patients with different types of CD and visceral leishmaniasis. Furthermore, the biosensor was stable for 5 days and presented a detection limit of 200 ng mL−1.

Investigation of Rotavirus infection in sheep usingserological and molecular techniques

2016 ◽  
Author(s):  
Volkan Yilmaz. ◽  
M.Ozkan Timurkan ◽  
Nuvit Coskun ◽  
Yakup Yildirim
Keyword(s):  
Molecular Detection ◽  
Molecular Techniques ◽  
Enzyme Linked Immunosorbent Assay ◽  
Small Scale ◽  
Family Farms ◽  
Rt Pcr ◽  
Fecal Samples ◽  
Rotavirus Infection ◽  
Scale Family ◽  
Polymerase Chain

In this study, serological and molecular research was conducted on the Rotavirus infection in domestic breeds of sheep at 2–3 years of age. The sheep included in the study were raised on small scale family units of less than 20 sheep per unit, in central Kars province and its districts (Susuz, Arpaçay, Kagizman and Selim) in the Northeast Anatolia region of Turkey. The blood and fecal samples were collected randomly from 450 sheep. They were analyzed for the presence of Rotavirus and the antibody against the virus using enzyme-linked immunosorbent assay (ELISA). The highest seropositive ratio (73.46%) was found in central Kars province. The seroprevalence of Rotavirus in sheep raised in the Kars region was determined to be 55.33%. Rotavirus was not detected in fecal samples with ELISA. Molecular detection of Rotavirus from fecal samples was done by reverse transcription polymerase chain reaction (RT-PCR) technique using specific generic primers for VP6 protein. Rotavirus could not be detected in RT-PCR. The data that were obtained showed that the infection spreads on small scale family farms. Based on this information, recommendations were made for controlling Rotavirus infection.

Sign in / Sign up

Export Citation Format

Share Document