261 research outputs found
The importance of the multidisciplinary approach to deal with the new epidemiological scenario of Chagas disease (global health)
There are currently two major factors that have modified the
epidemiology of Chagas disease in the last decades: climate
change and migration flows. In this new scenario, there are new
challenges to control and prevent Trypanosoma cruzi infection in
endemic countries, such as the control of a wider distribution
of triatomine vectors or the reinforcement of vertical
transmission programs. In non-endemic areas, few countries are
aware of the emergence of this new disease and have established
changes in their health systems. To address this new public
health challenge, the priorities should be control programs to
avoid new cases of T. cruzi infection acquired through vertical
transmission, blood transfusion or organ transplant. In both,
endemic and non-endemic areas, the international community and
all the actors involved in Chagas disease must join efforts
mainly in two directions: better management of the infection in
affected individuals and more research to cover the knowledge
gap mainly in physiopathology, diagnosis and treatment
Organització d'atencions de salut primària (ASP) en un hospital Rwandès. L'experiència d'un cooperador
'Hi ha la impressió generalitzada que la qualitat científica de la formació mèdica i pràctica de la medicina depèn d'una manera o d'una altra de l'important paper que té el laboratori. I no és així. La ciència, essencialment, és : observació, deducció, verificació i generalització'. (Abrahan Flexner. Medical education a comparative study. Nova York, Mac Millan, 1925.) L'antic concepte que diu que el metge existeix perquè pugui atendre el pacient que li demana les seves atencions està, avui superat. El nostre deure moral és d'assegurar-nos que les atencions mèdiques estiguin a la disposició de tota la població i que es promogui el concepte modern de salut tal com es contempla en la constitució de l'Organització Mundial de la Salut
Molecular diagnostics for Chagas disease: up to date and novel methodologies
Chagas disease is caused by the parasite Trypanosoma cruzi. It affects 7 million people, mainly in Latin America. Diagnosis is usually made serologically, but at some clinical scenarios serology cannot be used. Then, molecular detection is required for early detection of congenital transmission, treatment response follow up, and diagnosis of immune-suppression reactivation. However, present tests are technically demanding and require well-equipped laboratories which make them unfeasible in low-resources endemic regions
Delayed haemolysis after artesunate therapy in a cohort of patients with severe imported malaria due to Plasmodium falciparum
INTRODUCTION: Delayed haemolytic anaemia is one of the more
frequent events after treatment with intravenous artesunate in
patients with severe malaria. Little is known about its
frequency and the outcomes of patients with this condition.
METHODS: A retrospective study was conducted to describe the
incidence of delayed haemolysis in a cohort of patients with
severe malaria by Plasmodium falciparum treated with artesunate
between August 2013 and July 2015. RESULTS: The study included
52 patients with malaria due to Plasmodium falciparum, with 21
having severe malaria. The majority were male (66.7%), and the
median age was 43 years. Four patients (19%) presented
post-artesunate delayed haemolysis 11-13 days from the
initiation of treatment. Two patients required hospital
admission and red blood cell transfusion. CONCLUSION:
Post-artesunate delayed haemolysis is frequent in patients with
severe malaria treated with intravenous artemisinins. These
patients should be monitored for 4 weeks after treatment is
started
Pulmonary Infiltrates and Eosinophilia in a 25-Year-Old Traveler
A 25-year-old Spanish male travelled to Senegal in September 2009, where he swam near the Dindefelo fresh-water falls. Five weeks later, he presented with fever, myalgia, and dry cough. His complete blood count showed a hemoglobin level of 157 g/L, platelet count of 123.000 platelets/µL, and a leukocyte count of 8.670 cells/µL, with 9% eosinophils. Malaria smear, blood cultures, and serologies for common viral and bacterial infections were negative. Titers of an indirect hemagglutination test for Schistosoma mansoni were 1∶80. The patient was treated with a single dose of praziquantel (40 mg/kg) and prednisone (30 mg) for three days. After treatment, the dry cough increased and he developed moderate dyspnea, with increasing malaise and myalgia. A second blood sample revealed eosinophilia of 1.200 cells/µL. A chest X-ray showed patchy infiltrates in both lungs (Figure 1), and a CT scan showed multiple peripheral bilateral pseudonodular lesions with surrounding ground-glass-opacity halo
Introducing automation to the molecular diagnosis of Trypanosoma cruzi infection: A comparative study of sample treatments, DNA extraction methods and real-time PCR assays
Background Polymerase chain reaction (PCR) has become a useful tool for the diagnosis of Trypanosoma cruzi infection. The development of automated DNA extraction methodologies and PCR systems is an important step toward the standardization of protocols in routine diagnosis. To date, there are only two commercially available Real-Time PCR assays for the routine laboratory detection of T. cruzi DNA in clinical samples: TCRUZIDNA.CE (Diagnostic Bioprobes Srl) and RealCycler CHAG (Progenie Molecular). Our aim was to evaluate the RealCycler CHAG assay taking into account the whole process. Methodology/Principal findings We assessed the usefulness of an automated DNA extraction system based on magnetic particles (EZ1 Virus Mini Kit v2.0, Qiagen) combined with a commercially available Real-Time PCR assay targeting satellite DNA (SatDNA) of T. cruzi (RealCycler CHAG), a methodology used for routine diagnosis in our hospital. It was compared with a well-known strategy combining a commercial DNA isolation kit based on silica columns (High Pure PCR Template Preparation Kit, Roche Diagnostics) with an in-house Real-Time PCR targeting SatDNA. The results of the two methodologies were in almost perfect agreement, indicating they can be used interchangeably. However, when variations in protocol factors were applied (sample treatment, extraction method and Real-Time PCR), the results were less convincing. A comprehensive fine-tuning of the whole procedure is the key to successful results. Guanidine EDTA-blood (GEB) samples are not suitable for DNA extraction based on magnetic particles due to inhibition, at least when samples are not processed immediately. Conclusions/Significance This is the first study to evaluate the RealCycler CHAG assay taking into account the overall process, including three variables (sample treatment, extraction method and Real-Time PCR). Our findings may contribute to the harmonization of protocols between laboratories and to a wider application of Real-Time PCR in molecular diagnostic laboratories associated with health centers.Fil: Abras, Alba. Universidad de Barcelona; España. Universidad de Girona; España. Instituto de Salud Global de Barcelona; EspañaFil: Ballart, Cristina. Universidad de Barcelona; España. Instituto de Salud Global de Barcelona; EspañaFil: Llovet, Teresa. Universitat Autònoma de Barcelona; España. Hospital de la Santa Creu I Sant Pau; EspañaFil: Roig, Carme. Hospital de la Santa Creu I Sant Pau; EspañaFil: Gutiérrez, Cristina. Hospital de la Santa Creu I Sant Pau; EspañaFil: Tebar, Silvia. Universidad de Barcelona; España. Instituto de Salud Global de Barcelona; EspañaFil: Berenguer, Pere. Hospital de la Santa Creu I Sant Pau; EspañaFil: Pinazo, María-Jesús. Instituto de Salud Global de Barcelona; EspañaFil: Posada, Elizabeth. Instituto de Salud Global de Barcelona; EspañaFil: Gascón, Joaquim. Instituto de Salud Global de Barcelona; EspañaFil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Gállego, Montserrat. Instituto de Salud Global de Barcelona; España. Universidad de Barcelona; EspañaFil: Muñoz, Carmen. Hospital de la Santa Creu I Sant Pau; España. Universitat Autònoma de Barcelona; Españ
Increased expression levels of the pvcrt-o and pvmdr1 genes in a patient with severe Plasmodium vivax malaria
<p>Abstract</p> <p>Background</p> <p>There are increasing reports of severe clinical cases exclusively associated with <it>Plasmodium vivax </it>infections. Notably, this severity has been recently suggested to be associated with chloroquine resistance.</p> <p>Patients</p> <p>Two different patients presented at the Hospital Clinic in Barcelona with <it>P. vivax </it>malaria episodes. One patient had severe symptoms and the other mild symptoms. Both patients traveled through the Brazilian Amazon (Manaus) in 2007. For both patients the current diagnosis of malaria was the first. Two other patients with mild symptoms presented to the "Centro de Pesquisa em Medicina Tropical", also in the Brazilian Amazon (Rondônia) in 2000.</p> <p>Methods</p> <p>To exclude the possibility that the patient's severe symptoms were due to <it>Plasmodium falciparum</it>, a nested PCR was performed. A magnetic method was used to purify <it>P. vivax </it>free of human leukocytes. Quantitative real-time PCR was performed to compare the transcript levels of two main transporters likely to be involved in chloroquine resistance in <it>P. vivax</it>, namely the <it>P. vivax </it>chloroquine resistance transporter, <it>pvcrt-o</it>, and the <it>P. vivax </it>multidrug resistance transporter, <it>pvmdr 1</it>.</p> <p>Results</p> <p>Results demonstrated that the severe clinical symptoms were exclusively due to <it>P. vivax</it>. The patient presented acute respiratory conditions requiring admission to the intensive care unit. The magnetic method showed highly purified infected-reticulocytes with mature stages. In addition, it was found that parasites obtained from the severe patient had up to 2.9-fold increase in <it>pvmdr1 </it>levels and up to 21.9-fold increase in <it>pvcrt-o </it>levels compared to expression levels of parasites from the other patients with mild symptoms.</p> <p>Conclusion</p> <p>This is the first clinical case of severe disease exclusively associated with vivax malaria in Spain. Moreover, these findings suggest that clinical severity could be associated with increased expression levels of parasite genes likely involved in chloroquine resistance. It is necessary to further explore the potential of <it>pvmdr1 </it>and particularly <it>pvcrt-o </it>expression levels as molecular markers of severe disease in <it>P. vivax</it>.</p
In silico Design of an Epitope-Based Vaccine Ensemble for Chagas Disease
Trypanosoma cruzi infection causes Chagas disease, which affects 7 million people
worldwide. Two drugs are available to treat it: benznidazole and nifurtimox. Although
both are efficacious against the acute stage of the disease, this is usually asymptomatic
and goes undiagnosed and untreated. Diagnosis is achieved at the chronic stage, when
life-threatening heart and/or gut tissue disruptions occur in ∼30% of those chronically
infected. By then, the drugs’ efficacy is reduced, but not their associated high toxicity.
Given current deficiencies in diagnosis and treatment, a vaccine to prevent infection
and/or the development of symptoms would be a breakthrough in the management
of the disease. Current vaccine candidates are mostly based on the delivery of single
antigens or a few different antigens. Nevertheless, due to the high biological complexity
of the parasite, targeting as many antigens as possible would be desirable. In this
regard, an epitope-based vaccine design could be a well-suited approach. With this
aim, we have gone through publicly available databases to identify T. cruzi epitopes
from several antigens. By means of a computer-aided strategy, we have prioritized a
set of epitopes based on sequence conservation criteria, projected population coverage
of Latin American population, and biological features of their antigens of origin. Fruit of
this analysis, we provide a selection of CD8+ T cell, CD4+ T cell, and B cell epitopes that
have <70% identity to human or human microbiome protein sequences and represent
the basis toward the development of an epitope-based vaccine against T. cruzi
Host-Derived Molecules as Novel Chagas Disease Biomarkers: Hypercoagulability Markers in Plasma
The most severe clinical symptomatology of Chagas disease
affects ~30% of those chronically infected with the Trypanosoma
cruzi parasite. The pathogenic mechanisms that lead to
life-threatening heart and gut tissue disruptions occur
"silently" for a longtime in a majority of cases. As a result,
despite there are several serological and molecular methods
available to diagnose the infection in its acute and chronic
stages, diagnosis is often achieved only after the onset of
clinical symptoms in the chronic phase of the disease.
Furthermore, although there are two drugs to treat it, the
assessment of their performance is impractical with current
parasite-derived diagnostics, and therapeutic efficacy cannot be
acknowledged in a timely manner.In this chapter we present two
procedures to measure host-derived molecules as surrogates of
therapeutic response against chronic T. cruzi infection. Their
outputs relate to the generation and activity of thrombin, a
major component of the blood coagulation cascade. This is due to
the fact that a hypercoagulability state has been described to
occur in chronic Chagas disease patients and revert after
treatment with benznidazole
European expert network on rare communicable diseases and other rare diseases linked to mobility and globalisation focused on health care provision (EURaDMoG) : a feasibility study
Introduction: In the current mobility and globalization context, there is a growing need to identify potential changes on the pattern of diseases in the European Union (EU)/European Economic Area (EEA) and provide accurate diagnosis and treatment for the population. The pattern of rare communicable diseases that can affect people returning to EU/EEA from travel abroad, visiting EU/EEA or establishing in the EU/EEA is of special relevance. The objective of this manuscript is to give an overview about the EURaDMoG study and discuss the feasibility of establishing a European network on rare communicable diseases and other rare conditions linked to mobility and globalization. Methods: We undertook a three-steps process where we first conducted a narrative review to estimate the prevalence and incidence and to list rare communicable and non-communicable diseases linked to mobility and globalization in the EU/EEA; second, we organized an international consultation workshop with experts in the diseases previously selected; and finally, the feasibility study analysed how successful a European expert network on rare diseases linked to mobility and globalization focused on health care provision would be, accounting for different operational and also sustainability criteria. Results: First, considering the areas or topics that the network should cover, it was concluded that communicable and non-communicable rare diseases linked to mobility and globalization should be differentiated. Second, since all non-communicable rare diseases linked to mobility and globalization identified are already covered by different European Reference Networks (ERNs), there is no need for them to be included in a new European network. Three scenarios were considered for establishing a potential European network for rare communicable diseases linked to Mobility and Globalisation with a focus on Health Care provision: 1) To maintain the current situation "Status Quo" scenario; 2) to create a specific European expert network (EEN) on rare communicable diseases linked to mobility and globalisation; 3) to develop a new ERN on communicable rare diseases linked to mobility and globalisation. Conclusions: Since the focus is the provision of health care, an ERN could have the potential to better boost the quality of care being facilitated by technological tools and online platforms that permit the safe and ethically acceptable exchange of data. However, this potential new network should not eclipse current existing networks and they should be complementary
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