Time filter

Source Type

Harhay M.O.,Population Studies Center | Olliaro P.L.,World Health Organization | Vaillant M.,Competence Center in Methodology and Statistics | Chappuis F.,University of Geneva | And 7 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2011

Drug-dosing recommendations for visceral leishmaniasis (VL) treatment are based on the patients' weight or age. A current lack of demographic and anthropometric data on patients hinders (1) the ability of health providers to properly prepare for patient management, (2) an informed drug procurement for disease control, and (3) the design of clinical trials and development of new drug therapies in the different endemic areas. We present information about the age, gender, weight, and height of 29,570 consecutive VL patients presenting to 20 locations in six geographic endemic regions of Brazil, East Africa, Nepal, and India between 1997 and 2009. Our compilation shows substantial heterogeneity in the types of patients seeking care for VL at the clinics within the different locations. This suggests that drug development, procurement, and perhaps even treatment protocols, such as the use of the potentially teratogenic drug miltefosine, may require distinct strategies in these geographic settings. Copyright © 2011 by The American Society of Tropical Medicine and Hygiene.


Harhay M.O.,University of Pennsylvania | Olliaro P.L.,World Health Organization | Olliaro P.L.,University of Oxford | Costa D.L.,Federal University of Piauí | And 3 more authors.
Trends in Parasitology | Year: 2011

Since the early 1980s, visceral leishmaniasis (VL) which is, in general, a rural zoonotic disease, has spread to the urban centers of the north, and now the south and west of Brazil. The principal drivers differ between cities, though human migration, large urban canid populations (animal reservoir), and a decidedly peripatetic and adaptable sand fly vector are the primary forces. The exact number of urban cases remains unclear as a result of challenges with surveillance. However, the number of urban cases registered continues to increase annually. Most control initiatives (e.g. culling infected dogs and household spraying to kill the sand fly) could be effective, but have proven hard to maintain at large scales due to logistical, financial and other reasons. In this article, the urbanization of VL in Brazil is reviewed, touching on these and other topics related to controlling VL within and outside Brazil. © 2011 Elsevier Ltd.


Introduction: Zoonotic kala-azar, a lethal disease caused by protozoa of the genus Leishmania is considered out of control in parts of the world, particularly in Brazil, where transmission has spread to cities throughout most of the territory and mortality presents an increasing trend. Although a highly debatable measure, the Brazilian government regularly culls seropositive dogs to control the disease. Since control is failing, critical analysis concerning the actions focused on the canine reservoir was conducted. Methods: In a review of the literature, a historical perspective focusing mainly on comparisons between the successful Chinese and Soviet strategies and the Brazilian approach is presented. In addition, analyses of the principal studies regarding the role of dogs as risk factors to humans and of the main intervention studies regarding the efficacy of the dog killing strategy were undertaken. Brazilian political reaction to a recently published systematic review that concluded that the dog culling program lacked efficiency and its effect on public policy were also reviewed. Results: No firm evidence of the risk conferred by the presence of dogs to humans was verified; on the contrary, a lack of scientific support for the policy of killing dogs was confirmed. A bias for distorting scientific data towards maintaining the policy of culling animals was observed. Conclusions: Since there is no evidence that dog culling diminishes visceral leishmaniasis transmission, it should be abandoned as a control measure. Ethical considerations have been raised regarding distorting scientific results and the killing of animals despite minimal or absent scientific evidence.


Costa C.H.N.,Federal University of Piauí | Ribeiro J.C.C.B.,Institute Doencas Tropicais Natan Portella | Nunes-Filho L.P.,Clinica de Imagem Lucidio Portella
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2013

Although cryptococcal infections begin in the lungs, meningoencephalitis is the most frequently encountered manifestation of cryptococcosis among individuals with advanced immunosuppression. As the infection progresses along the Virchow-Robin spaces, these structures may become dilated with mucoid material produced by the capsule of the organism. We report a case of a 24-year-old man with cryptococcal meningoencephalitis in which magnetic resonance imaging showed clusters of gelatinous pseudocysts in the periventricular white matter, basal ganglia, mammillary bodies, midbrain peduncles and nucleus dentatus with a soap bubble appearance.


Silva J.M.,Institute Doencas Tropicais Natan Portella | Zacarias D.A.,Federal University of Paraiba | De Figueiredo L.C.,Federal University of Piauí | Soares M.R.A.,Federal University of Pará | And 3 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2014

Kala-azar or visceral leishmaniasis, found mostly throughout the Indian Subcontinent, East Africa, and Brazil, kills 20,000-40,000 persons annually. The agents, Leishmania donovani and Leishmania infantum, are obligatory intracellular protozoa of mononuclear phagocytes found principally in the spleen and bone marrow. Protracted fever, anemia, wasting, hepatosplenomegaly, hemorrhages, and bacterial co-infections are typical features. One hundred and twenty-two (122) in-hospital patients were studied to verify if higher bone marrow parasite load estimated by quantitative polymerase chain reaction is associated with severe disease. The estimated median parasite load was 5.0 parasites/106 human nucleated cells. It is much higher in deceased than among survivors (median 75.0 versus 4.2). Patients who lost more weight had a higher parasite burden, as well as patients with epistaxis, abdominal pain, edema, and jaundice. This study suggests that higher parasite load is influenced by wasting, which may lead to more severe disease. Copyright © 2014 by The American Society of Tropical Medicine and Hygiene.


Alonso D.P.,São Paulo State University | Costa D.L.,Institute Doencas Tropicais Natan Portella | De Mendonca I.L.,Federal University of Piauí | Costa C.H.N.,Institute Doencas Tropicais Natan Portella | Ribolla P.E.M.,São Paulo State University
American Journal of Tropical Medicine and Hygiene | Year: 2010

Leishmania infantum chagasi is the causative agent of visceral leishmaniasis in Brazil. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of kinetoplast DNA (kDNA) minicircles was used to evaluate genetic profiles of 48 Leishmania infantum chagasi strains from dog and human parasite cultures, fresh collected dog bone marrow aspirates, and from infected sand flies. Results revealed that heterogeneity in kDNA minicircles depends mostly on the source of the samples, with cultured parasites showing a high degree of homogeneity. Copyright © 2010 by The American Society of Tropical Medicine and Hygiene.


PubMed | Institute Doencas Tropicais Natan Portella, Federal University of Piauí and Federal University of Ceará
Type: Journal Article | Journal: Arquivos de neuro-psiquiatria | Year: 2015

To verify the relationship between intracranial pressure and flash visual evoked potentials (F-VEP) in patients with cryptococcal meningitis. Method The sample included adults diagnosed with cryptococcal meningitis admitted at a reference hospital for infectious diseases. The patients were subjected to F-VEP tests shortly before lumbar puncture. The Pearsons linear correlation coefficient was calculated and the linear regression analysis was performed.Eighteen individuals were subjected to a total of 69 lumbar punctures preceded by F-VEP tests. At the first lumbar puncture performed in each patient, N2 latency exhibited a strong positive correlation with intracranial pressure (r = 0.83; CI = 0.60 - 0.94; p < 0.0001). The direction of this relationship was maintained in subsequent punctures.The intracranial pressure measured by spinal tap manometry showed strong positive association with the N2 latency F-VEP in patients with cryptococcal meningitis.


PubMed | Institute Doencas Tropicais Natan Portella, São Paulo State University, Superintendencia de Controle de Endemias SUCEN, Federal University of Piauí and Federal University of Mato Grosso do Sul
Type: | Journal: BioMed research international | Year: 2016

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in the Americas with domestic dogs being its major reservoir hosts. The main VL vector is the sandfly Lutzomyia longipalpis, while other Lutzomyia species may play a role in disease transmission. Although the genetic structure of L. infantum populations has been widely evaluated, only a few studies have addressed this subject coupled to the genetic structure of the respective sandfly vectors. In this study, we analyzed the population structure of L. infantum in three major VL endemic areas in Brazil and associated it with Lutzomyia longipalpis geographic structure.


PubMed | University of Porto, Institute Doencas Tropicais Natan Portella and Federal University of Piauí
Type: Journal Article | Journal: Nanomedicine : nanotechnology, biology, and medicine | Year: 2014

Leishmaniasis is one of the most serious diseases in the world and can be lethal if untreated. This is especially the case for visceral leishmaniasis, which is commonly caused by Leishmania (L.) infantum and for which available medication is still inadequate. A recently described antimicrobial peptide DRS 01 has been reported to kill L. infantum promastigotes, but nothing is known about its mode of action or effect on the cell. In this paper we report the visualization of the interaction between DRS 01 and L. infantum promastigotes using two high resolution microscopic techniques: atomic force microscopy and scanning electron microscopy. The results show considerable morphological changes at and above the IC50 in the treated cells. Both membrane damage and flagella alterations were observed. The results strongly suggest a membrane-directed action for DRS 01 on the Leishmania species studied.In this paper, the effects of DRS 01, an antimicrobial peptide, is studied in Leishmania infantum using atomic force microscopy as well as standard scanning electron microscopy techniques, with the conclusion of a membrane-based effect by DRS 01 on the parasites.


PubMed | Institute Doencas Tropicais Natan Portella, Federal University of Piauí and Federal University of Minas Gerais
Type: Journal Article | Journal: Revista da Sociedade Brasileira de Medicina Tropical | Year: 2016

Early identification of patients at higher risk of progressing to severe disease and death is crucial for implementing therapeutic and preventive measures; this could reduce the morbidity and mortality from kala-azar. We describe a score set composed of four scales in addition to software for quick assessment of the probability of death from kala-azar at the point of care.Data from 883 patients diagnosed between September 2005 and August 2008 were used to derive the score set, and data from 1,031 patients diagnosed between September 2008 and November 2013 were used to validate the models. Stepwise logistic regression analyses were used to derive the optimal multivariate prediction models. Model performance was assessed by its discriminatory accuracy. A computational specialist system (Kala-Cal(r)) was developed to speed up the calculation of the probability of death based on clinical scores.The clinical prediction score showed high discrimination (area under the curve [AUC] 0.90) for distinguishing death from survival for children 2 years old. Performance improved after adding laboratory variables (AUC 0.93). The clinical score showed equivalent discrimination (AUC 0.89) for older children and adults, which also improved after including laboratory data (AUC 0.92). The score set also showed a high, although lower, discrimination when applied to the validation cohort.This score set and Kala-Cal(r) software may help identify individuals with the greatest probability of death. The associated software may speed up the calculation of the probability of death based on clinical scores and assist physicians in decision-making.

Loading Institute Doencas Tropicais Natan Portella collaborators
Loading Institute Doencas Tropicais Natan Portella collaborators