scholarly journals Sensitive Molecular Diagnostics for Cutaneous Leishmaniasis

2017 ◽  
Vol 4 (2) ◽  
Author(s):  
Orli Sagi ◽  
Anat Berkowitz ◽  
Shlomi Codish ◽  
Victor Novack ◽  
Aviv Rashti ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Leishmania Major ◽  
Point Of Care ◽  
Leishmania Species ◽  
Rapid Diagnosis ◽  
Clinical Samples ◽  
Leishmania Braziliensis ◽  
Multiplex Qpcr ◽  
Highly Sensitive ◽  
Pcr Multiplex

Abstract Background Rapid diagnosis of cutaneous leishmaniasis (CL) and identification of Leishmania species is highly important for the disease management. In Israel, CL is caused mainly by Leishmania major and Leishmania tropica species. Methods We established an easy to handle point of care lesion-swabbing, combined with a highly sensitive multiplex real time PCR (multiplex qPCR) for accurate and rapid diagnosis of Leishmania species. Results Using three probes: one general for: Leishmania species, and two specific for L major, and L tropica, we screened 1783 clinical samples collected during two years. Leishmania species was found in 1086 individuals, 1008 L major, and 70 L tropica. Eight samples positive for Leishmania species only, were further tested using a second set of multiplex qPCR developed, and were found positive for Leishmania braziliensis and Leishmania infantum/donovani (2 and 6 samples, concomitantly). Conclusions Taken together, the test enabled diagnostics and better treatment of Leishmania infections from the Old World (1078 samples) and the New World (8 samples), and the subtyping of the dominant strains in the region, as well as in returning travelers’.

scholarly journals Variable gene expression and parasite load predict treatment outcome in cutaneous leishmaniasis

2019 ◽  
Vol 11 (519) ◽  
pp. eaax4204 ◽  
Author(s):  
Camila Farias Amorim ◽  
Fernanda O. Novais ◽  
Ba T. Nguyen ◽  
Ana M. Misic ◽  
Lucas P. Carvalho ◽  
...  
Keyword(s):  
Treatment Outcome ◽  
Treatment Failure ◽  
Cutaneous Leishmaniasis ◽  
Point Of Care ◽  
Parasite Load ◽  
Clinical Samples ◽  
Leishmania Braziliensis ◽  
Variable Expression ◽  
Pentavalent Antimony ◽  
Marker Profile

Patients infected with Leishmania braziliensis develop chronic lesions that often fail to respond to treatment with antiparasite drugs. To determine whether genes whose expression is highly variable in lesions between patients might influence disease outcome, we obtained biopsies of lesions from patients before treatment with pentavalent antimony and performed transcriptomic profiling on these clinical samples. We identified genes that were highly variably expressed between patients, and the variable expression of these genes correlated with treatment outcome. Among the most variable genes in all the patients were components of the cytolytic pathway, and the expression of these genes correlated with parasite load in the skin. We demonstrated that treatment failure was linked to the cytolytic pathway activated during infection. Using a host-pathogen marker profile of as few as three genes, we showed that eventual treatment outcome could be predicted before the start of treatment in two separate cohorts of patients with cutaneous leishmaniasis (n = 21 and n = 25). These findings raise the possibility of point-of-care diagnostic screening to identify patients at high risk of treatment failure and provide a rationale for a precision medicine approach to drug selection in cutaneous leishmaniasis. This work more broadly demonstrates the value of identifying genes of high variability in other diseases to better understand and predict diverse clinical outcomes.

scholarly journals Efficacy and Tolerability of Miltefosine in the Treatment of Cutaneous Leishmaniasis

2020 ◽  
Author(s):  
JeanAnne M Ware ◽  
Elise M O’Connell ◽  
Thomas Brown ◽  
Lauren Wetzler ◽  
Kawsar R Talaat ◽  
...  
Keyword(s):  
Adverse Events ◽  
Cutaneous Leishmaniasis ◽  
Leishmania Major ◽  
Standard Of Care ◽  
Leishmania Species ◽  
Response To Treatment ◽  
Prior History ◽  
Leishmania Braziliensis ◽  
Alternative Treatment Option ◽  
Leishmania Panamensis

Abstract Background Cutaneous leishmaniasis (CL) is a neglected tropical disease causing an estimated 1 million new cases annually. While antimonial compounds are the standard of care worldwide, they are associated with significant adverse effects. Miltefosine, an oral medication, is United States (US) Food and Drug Administration approved to treat CL caused by Leishmania braziliensis, Leishmania guyanensis, and Leishmania panamensis. Evidence of efficacy in other species and side-effect profiles in CL has been limited. Methods Twenty-six patients with CL were treated with miltefosine at the US National Institutes of Health. Species included L. braziliensis (n = 7), L. panamensis (n = 5), Leishmania mexicana (n = 1), Leishmania infantum (n = 3), Leishmania aethiopica (n = 4), Leishmania tropica (n = 2), Leishmania major (n = 1), and unspeciated (n = 3). Demographic and clinic characteristics of the participants, response to treatment, and associated adverse events were analyzed. Results Treatment with miltefosine resulted in cure in 77 % (20/26) of cases, with cures among all species. Common adverse events included nausea/vomiting (97%) and lack of appetite (54%). Clinical management or dose reduction was required in a third of cases. Gout occurred in 3 individuals with a prior history of gout. Most laboratory abnormalities, including elevated creatinine and aminotransferases, were mild and normalized after treatment. Conclusions Our data suggest that miltefosine has good but imperfect efficacy to a wide variety of Leishmania species. While side effects were common and mostly mild to moderate, some resulted in discontinuation of therapy. Due to oral administration, broad efficacy, and manageable toxicities, miltefosine is a viable alternative treatment option for CL, though cost and lack of local availability may limit its widespread use.

scholarly journals Evaluation of mobile real-time polymerase chain reaction tests for the detection of severe acute respiratory syndrome coronavirus 2

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chukwunonso Onyilagha ◽  
Henna Mistry ◽  
Peter Marszal ◽  
Mathieu Pinette ◽  
Darwyn Kobasa ◽  
...  
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Real Time ◽  
Point Of Care ◽  
Middle Eastern ◽  
Turnaround Time ◽  
Cross Reactivity ◽  
Clinical Samples ◽  
Diarrhea Virus ◽  
Highly Sensitive ◽  
Transmissible Gastroenteritis

AbstractThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), calls for prompt and accurate diagnosis and rapid turnaround time for test results to limit transmission. Here, we evaluated two independent molecular assays, the Biomeme SARS-CoV-2 test, and the Precision Biomonitoring TripleLock SARS-CoV-2 test on a field-deployable point-of-care real-time PCR instrument, Franklin three9, in combination with Biomeme M1 Sample Prep Cartridge Kit for RNA 2.0 (M1) manual extraction system for rapid, specific, and sensitive detection of SARS-COV-2 in cell culture, human, and animal clinical samples. The Biomeme SARS-CoV-2 assay, which simultaneously detects two viral targets, the orf1ab and S genes, and the Precision Biomonitoring TripleLock SARS-CoV-2 assay that targets the 5′ untranslated region (5′ UTR) and the envelope (E) gene of SARS-CoV-2 were highly sensitive and detected as low as 15 SARS-CoV-2 genome copies per reaction. In addition, the two assays were specific and showed no cross-reactivity with Middle Eastern respiratory syndrome coronavirus (MERS-CoV), infectious bronchitis virus (IBV), porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis (TGE) virus, and other common human respiratory viruses and bacterial pathogens. Also, both assays were highly reproducible across different operators and instruments. When used to test animal samples, both assays equally detected SARS-CoV-2 genetic materials in the swabs from SARS-CoV-2-infected hamsters. The M1 lysis buffer completely inactivated SARS-CoV-2 within 10 min at room temperature enabling safe handling of clinical samples. Collectively, these results show that the Biomeme and Precision Biomonitoring TripleLock SARS-CoV-2 mobile testing platforms could reliably and promptly detect SARS-CoV-2 in both human and animal clinical samples in approximately an hour and can be used in remote areas or health care settings not traditionally serviced by a microbiology laboratory.

scholarly journals Low Plasma Membrane Expression of the Miltefosine Transport Complex Renders Leishmania braziliensis Refractory to the Drug

2009 ◽  
Vol 53 (4) ◽  
pp. 1305-1313 ◽  
Author(s):  
María P. Sánchez-Cañete ◽  
Luís Carvalho ◽  
F. Javier Pérez-Victoria ◽  
Francisco Gamarro ◽  
Santiago Castanys
Keyword(s):  
Plasma Membrane ◽  
Cutaneous Leishmaniasis ◽  
Oral Drug ◽  
Leishmania Braziliensis ◽  
Β Subunit ◽  
Membrane Expression ◽  
Plasma Membrane Expression ◽  
Highly Sensitive ◽  
P Type ◽  
Transport Complex

ABSTRACT Miltefosine (hexadecylphosphocholine, MLF) is the first oral drug with recognized efficacy against both visceral and cutaneous leishmaniasis. However, some clinical studies have suggested that MLF shows significantly less efficiency against the cutaneous leishmaniasis caused by Leishmania braziliensis. In this work, we have determined the cellular and molecular basis for the natural MLF resistance observed in L. braziliensis. Four independent L. braziliensis clinical isolates showed a marked decrease in MLF sensitivity that was due to their inability to internalize the drug. MLF internalization in the highly sensitive L. donovani species requires at least two proteins in the plasma membrane, LdMT, a P-type ATPase involved in phospholipid translocation, and its β subunit, LdRos3. Strikingly, L. braziliensis parasites showed highly reduced levels of this MLF translocation machinery at the plasma membrane, mainly because of the low expression levels of the β subunit, LbRos3. Overexpression of LbRos3 induces increased MLF sensitivity not only in L. braziliensis promastigotes but also in intracellular amastigotes. These results further highlight the importance of the MLF translocation machinery in determining MLF potency and point toward the development of protocols to routinely monitor MLF susceptibility in geographic areas where L. braziliensis might be prevalent.

scholarly journals DETECTION OF PRO- INFLAMMATORY INTERLEUKIN 17 IN PATIENTS WITH L. TROPICA IN THI-QAR PROVINCE, IRAQ

2020 ◽  
Vol 17 (36) ◽  
pp. 949-957
Author(s):  
Mohammed Hassan FLAIH ◽  
Fadhil Abbas AL-ABADY ◽  
Khwam Reissan HUSSEIN
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Nested Pcr ◽  
Accurate Method ◽  
Leishmania Species ◽  
Clinical Samples ◽  
Interleukin 17 ◽  
Infected Female ◽  
Endemic Diseases ◽  
Leishmania Spp ◽  
South Of Iraq

Cutaneous leishmaniasis (CL) is a widespread health problem and considered one of the endemic diseases in Iraq. The dermal lesion occurs due to an obligate intracellular Leishmania parasite, which transmits by the bite of the infected female sandfly. This study aims to identify Leishmania species in Thi-Qar province/South of Iraq and detect IL-17 level in serum of infected patients with L. tropica. The study was conducted in three local locations, Al-Hussein Teaching, Al-Suq Al-Shyokh General, and Al-Shatrah General Hospitals in the province for the period from the beginning of November 2018 to the end of October 2019. After clinical diagnosis, eighty out of two hundred forty-seven samples were selected for molecular examination by nested-PCR technique, where the lesion edge was injected by normal saline and pulled again to obtain the parasite DNA. Also, a measure of the IL-17 concentration level in serum of the patients with ELISA. The findings of the electrophoresis of the kinetoplast minicircle DNA gene showed that 65 samples were positive for cutaneous leishmaniasis, and observed two species of Leishmania spp. in the study area, 46 (57.5%) samples were L. tropica at 750 bp and 19 (23.75%) samples were L. major. Serum IL-17 concentration recorded a significant increase among patients infected with L. tropica at different infection stages than control samples. Generally, the Nested-PCR technique is an accurate method for diagnosing clinical samples and molecular determination of Leishmania parasites. L. tropica is the dominant specie that caused CL in Thi-Qar province, while L. major recorded a low incidence.

scholarly journals Molecular Identification of Species Caused Cutaneous Leishmaniasis in Southern Zone of Iran

2019 ◽  
Author(s):  
Afshin Barazesh ◽  
Mohammad Hossein Motazedian ◽  
Moradali Fouladvand ◽  
Gholamreza Hatam ◽  
Saeed Tajbakhsh ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Leishmania Major ◽  
Synergistic Effects ◽  
Leishmania Species ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Skin Ulcers ◽  
Identification Of Species ◽  
Main Factor

Background: Leishmania major and Leishmania tropica are two main species causing cutaneous leishmaniasis (CL) in Iran. Recently, Crithidia spp. has also been reported in the wound of patients with CL. In this study, we determined the species causing CL in the southern of Iran and the role of Crithidia spp. in creating skin ulcers. Methods: In this cross-sectional study from Apr to Sep 2016, 66 patients with CL referred to Diagnostic Lab of Leishmaniasis, Valfajr Health Center, Shiraz, Iran, were selected. After DNA extraction from the Giemsa stained smears, all samples were amplified in two separate steps using specific primers, firstly, to differentiate Leishmania species and then to identify Crithidia spp. Results: Two species L. major and L. tropica were responsible for 60 and 6 cases, respectively. Moreover, in two patients, mixed infection with Crithidia was confirmed. In mix infection cases, the morphology of the cutaneous ul­cers was not different from the wounds of other patients. Conclusion: Leishmania major is responsible for the most common CL in southern Iran. In addition, in two patients with L. major and L. tropica, mix infection with Crithidia was confirmed. The potential role of Crithidia as the main factor for CL and the probability of this parasite to have synergistic effects on Leishmania, as a hypothesis, requires more comprehensive researches on the ambiguity of this protozoon.

scholarly journals SARS-CoV-2 multi-variant graphene biosensor based on engineered dimeric ACE2 receptor

2021 ◽  
Author(s):  
Mattia D'Agostino ◽  
Eleonora Pavoni ◽  
Alice Romagnoli ◽  
Chiara Ardiccioni ◽  
Stefano Motta ◽  
...  
Keyword(s):  
Point Of Care ◽  
Host Cells ◽  
Clinical Samples ◽  
Detection Systems ◽  
Graphene Field Effect Transistor ◽  
Highly Sensitive ◽  
Care Systems ◽  
Point Of Care Systems ◽  
Computational Analyses

Fast, reliable and point-of-care systems to detect the SARS-CoV-2 infection are crucial to contain viral spreading and to adopt timely clinical treatments. Many of the rapid detection tests currently in use are based on antibodies that bind viral proteins. However, newly appearing virus variants accumulate mutations in their RNA sequence and produce proteins, such as Spike, that may show reduced binding affinity to these diagnostic antibodies, resulting in less reliable tests and in the need for continuous update of the sensing systems. Here we propose a graphene field-effect transistor (gFET) biosensor which exploits the key interaction between the Spike protein and the human ACE2 receptor. This interaction is one of the determinants of host infections and indeed recently evolved Spike variants were shown to increase affinity for this receptor. Through extensive computational analyses we show that a chimeric ACE2-Fc construct mimics the ACE2 dimer, normally present on host cells membranes, better than its soluble truncated form. We demonstrate that ACE2-Fc functionalized gFET is effective for in vitro detection of Spike and outperforms the same chip functionalized with either a diagnostic antibody or the soluble ACE2. Our sensor is implemented in a portable, wireless, point-of-care device and successfully detected both alpha and gamma virus variants in patient clinical samples. As incomplete immunization, due to vaccine roll-out, may offer new selective grounds for antibody-escaping virus variants, our biosensor opens to a class of highly sensitive and variant-robust SARS-CoV-2 detection systems.

scholarly journals SARS-CoV-2 antigen rapid diagnostic test enhanced with silver amplification technology

2021 ◽  
Author(s):  
Kei Miyakawa ◽  
Rikako Funabashi ◽  
Yutaro Yamaoka ◽  
Sundararaj Stanleyraj Jeremiah ◽  
Junichi Katada ◽  
...  
Keyword(s):  
Diagnostic Test ◽  
Rapid Diagnostic Test ◽  
Point Of Care ◽  
Rapid Diagnosis ◽  
Clinical Samples ◽  
Nasopharyngeal Swab ◽  
Special Equipment ◽  
Viral Spread ◽  
Silver Amplification ◽  
Low Sensitivity

AbstractRapid diagnosis of COVID-19 is essential for instituting measures to prevent viral spread. SARS-CoV-2 antigen rapid diagnostic test (Ag-RDT) based on lateral flow immunochromatography assay (LFIA) principle can visually indicate the presence of SARS-CoV-2 antigens as a band. Ag-RDT is clinically promising as a point-of-care testing because it can give results in a short time without the need for special equipment. Although various antigen capture LFIAs are now available for rapid diagnosis for SARS-CoV-2 infection, they face the problems of low sensitivity. We have previously developed highly specific monoclonal antibodies (mAb) against SARS-CoV-2 nucleocapsid protein (NP) and in this study, we have employed these mAbs to develop a new LFIA that can detect SARS-CoV-2 NP in nasopharyngeal swab samples with higher sensitivity by combining them with silver amplification technology. We also compared the performance of our Ag-RDT against the commercially available Ag-RDTs using clinical samples to find that our newly developed LFIA performed best among tested, highlighting the superiority of silver amplification technology.

scholarly journals Analysis of the Immune Responses of Mice to Infection with Leishmania braziliensis

1998 ◽  
Vol 66 (2) ◽  
pp. 827-829 ◽  
Author(s):  
Gregory K. DeKrey ◽  
Hermenio C. Lima ◽  
Richard G. Titus
Keyword(s):  
Immune Responses ◽  
Cutaneous Leishmaniasis ◽  
Leishmania Major ◽  
Gamma Interferon ◽  
Interleukin 4 ◽  
Leishmania Braziliensis ◽  
Dependent Mechanism

ABSTRACT Leishmania major and Leishmania braziliensis both cause cutaneous leishmaniasis, but the former kills BALB/c mice while the latter is killed by the mice. This killing of L. braziliensis occurred by a gamma interferon-dependent mechanism, potentially made possible by the observed lack of high interleukin-4 production.

scholarly journals Molecular Characterisation of Leishmania Species from Stray Dogs and Patients in Saudi Arabia

2020 ◽  
Author(s):  
Abdullah D Alanazi ◽  
Abdulazi S Alouffi ◽  
Mohamed S Alyousif ◽  
Abdulsadah A Rahi ◽  
Magda A Ali ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Cutaneous Leishmaniasis ◽  
Leishmania Major ◽  
Leishmania Species ◽  
Sand Fly ◽  
Human Populations ◽  
Nested Polymerase Chain Reaction ◽  
Stray Dogs ◽  
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 they occur in sympatry, the role of each species of Leishmania in the epidemiology of cutaneous leishmaniasis (CL) is not clear. Methods: To determine the frequency of occurrence and to identify the species of Leishmania that infect humans and stray dogs in Riyadh and Al-Qaseem (Saudi Arabia), 311 stray dogs and 27 human patients who were suspected for Leishmania were examined for CL by a nested polymerase chain reaction (nPCR).Results: The use of nPCR detected seven patients (25.9%) who were positive for cutaneous leishmaniasis. Five patients from Riyadh were infected by L. major and two from Al-Qaseem 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 to be conducted in Saudi Arabia. The relationship between the sand-fly vectors and the reservoirs of both Leishmania spp. is still scarcely known in this region, and epidemiological investigations are required in order to progress towards control and prevention of the infection in canine and human populations.

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