Fred Luciano Neves Santos

Fundação Oswaldo Cruz

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Leonardo Maia Leony

Fundação Oswaldo Cruz

ÂA

Ângelo Antônio Oliveira Silva

Fundação Oswaldo Cruz

Paola Alejandra Fiorani Celedón

Instituto de Biologia Molecular do Paraná

Nilson Ivo Tonin Zanchin

Fundação Carlos Chagas

Natália Erdens Maron Freitas

Fundação Oswaldo Cruz

Ramona Tavares Daltro

Fundação Oswaldo Cruz

Emily Ferreira dos Santos

Fundação Oswaldo Cruz

Larissa de Carvalho Medrado Vasconcelos

Fundação Oswaldo Cruz

Marco Aurélio Krieger

Fundação Carlos Chagas

Mitermayer Galvão dos Reis

Yale University

Cooperative Institutions

Fundação Oswaldo Cruz

145

Universidade Federal da Bahia

Escola Bahiana de Medicina e Saúde Pública

Hospital Ana Nery

Universidade Federal de Minas Gerais

Ministério da Saúde

Universidade de São Paulo

Fundação Carlos Chagas

Complexo Hospitalar Universitário Professor Edgard Santos

Universidade do Estado da Bahia

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Evaluation of nonpolar lipid extract antigen-based enzyme-linked immunosorbent assay for the serodiagnosis of tuberculosis

Diagnostic Microbiology and Infectious Disease (2024)

Luana E. Araújo Jéssica Dias Petrilli Carlos R. Oliveira Thainá Horta Paulo Estevão

10.1016/j.diagmicrobio.2024.116560

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Meloidogyne eggs in human stool in Northeastern Brazil

Revista da Sociedade Brasileira de Medicina Tropical (2016)

Fred Luciano Neves Santos Alina Maria Gonzaga Carlos de Souza Filipe Dantas‐Torres

Root-knot nematodes (Meloidogyne spp.) are among the most economically damaging genera of plant-parasitic nematodes worldwide(1). Although they are not pathogenic to humans, their eggs may eventually be found in human stools(2) and owing to their similarity with eggs of pathogenic nematodes must be correctly identifi ed to avoid unnecessary treatments.

10.1590/0037-8682-0110-2016

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Citations (1)

A multicenter comparative study of the performance of four rapid immunochromatographic tests for the detection of anti-Trypanosoma cruzi antibodies in Brazil

Frontiers in Medicine (2023)

Jacqueline Araújo Domingos Iturra Leonardo Maia Leony Fernanda Alvarenga Cardoso Medeiros Job Alves de Souza Filho Liliane da Rocha Siriano

Diagnosis of Trypanosoma cruzi ( T. cruzi ) infection in the chronic phase of Chagas disease (CD) is performed by serologic testing. Conventional tests are currently used with very good results but require time, laboratory infrastructure, and expertise. Rapid diagnostic tests (RDTs) are an alternative as the results are immediate and do not require specialized knowledge, making them suitable for epidemiologic studies and promising as a screening tool. Nevertheless, few studies conducted comparative evaluations of RDTs to validate the results and assess their performance. In this study, we analyzed four trades of rapid tests (OnSite Chagas Ab Combo Rapid Test-United States, SD Bioline Chagas AB-United States, WL Check Chagas-Argentina, and TR Chagas Bio-Manguinhos-Brazil) using a panel of 190 samples, including sera from 111 infected individuals, most of whom had low T. cruzi antibody levels. An additional 59 samples from uninfected individuals and 20 sera from individuals with other diseases, mainly visceral leishmaniasis, were included. All tests were performed by three independent laboratories in a blinded manner. Results showed differences in sensitivity from 92.8 to 100%, specificity from 78.5 to 92.4%, and accuracy from 90.5 to 95.3% among the four assays. The results presented here show that all four RDTs have high overall diagnostic ability. However, WL Check Chagas and TR Chagas Bio-Manguinhos were considered most suitable for use in screening studies due to their high sensitivity combined with good performance. Although these two RDTs have high sensitivity, a positive result should be confirmed with other tests to confirm or rule out reactivity/positivity, especially considering possible cross-reactivity with individuals with leishmaniasis or toxoplasmosis.

Chagas Disease

10.3389/fmed.2023.1031455

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Evidence of New Endemic Clusters of Human T-Cell Leukemia Virus (HTLV) Infection in Bahia, Brazil

Frontiers in Microbiology (2019)

Felicidade Mota Pereira Maria da Conceição Chagas de Almeida Fred Luciano Neves Santos Roberto Carreiro Carlos Gustavo Régis-Silva

Background: Salvador, Bahia (northeastern Brazil), has been identified as the epicenter of Human T-cell leukemia virus Human T-cell leukemia virus (HTLV) type 1 infection in the country. This study aims to estimate the rate of HTLV infection and the geographical distribution of this virus in this state. Methods All HTLV tests (chemiluminescence/ELISA assays/Western Blotting) performed in the Central Laboratory of Public Health of Bahia (LACEN) from 2004 to 2013 were included. Data was extracted from LACEN's database using high volume extract, transformation and load throughput. Infection rate was expressed as the number of infected individuals per 100,000 inhabitants considering municipalities grouped in microregions and/or mesoregions as the unit of analysis. Results A total of 233,876 individuals were evaluated. Individuals were from 394 out of 417 municipalities of Bahia (94.5%). HTLV chemiluminescence/ELISA assay was found to be reactive for 3,138 individuals from whom 2,323 had WB results (1,978 positives, 62 negative and 282 indeterminate). Out of 1978 reactive samples, 1,813 (91.7%) were positive for HTLV-1, 58 (2.9%) for HTLV-2 and 107 (5.4%) were for both HTLV-1 and HTLV-2. The cumulative mean rate of HTLV-positive cases in Bahia was 14.4 per 100,000 inhabitants. Three microregions presented rates > 20 HTLV-positive cases/100,000 inhabitants: Barreiras (24.83 cases per 100,000 inhabitants), Salvador (22.90 cases per 100,000 inhabitants), and Ilhéus-Itabuna (22.60 cases per 100,000 inhabitants). Conclusion HTLV infection is disseminated in the state of Bahia, with an overall moderate rate of infection. Further studies should be conducted to characterize the epidemiological and clinical profile of HTLV-infected individuals better and to propose effective prevention measures.

Infection rate

10.3389/fmicb.2019.01002

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Citations (29)

Mecanismos fisiopatogênicos e diagnóstico laboratorial da infecção causada pela Entamoeba histolytica

Jornal Brasileiro de Patologia e Medicina Laboratorial (2008)

Fred Luciano Neves Santos Neci Matos Soares

A amebíase é a segunda causa de morte entre as doenças parasitárias no mundo. Seu agente etiológico é o protozoário Entamoeba histolytica, que através da secreção de proteinases é capazes de destruir o tecido hospedeiro, matando as células-alvo por contato e fagocitando eritrócitos. Dessa forma, os trofozoítos invadem a mucosa intestinal, provocando a colite amebiana. Em alguns casos atravessam a mucosa e, através da circulação porta, chegam ao fígado, onde causam necrose constituída por poucos trofozoítos rodeados de hepatócitos mortos e debris celulares liquefeitos. Essa invasão está diretamente relacionada com a capacidade de síntese e a secreção de moléculas responsáveis pela virulência dos trofozoítos, como os amebaporos, as lectinas e as cisteína proteinases. O diagnóstico da infecção causada pelo patógeno é rotineiramente realizado através da microscopia óptica de amostras frescas ou espécimes fixados. Entretanto essa metodologia apresenta limitações, sendo incapaz de distinguir as espécies pertencentes ao complexo E. histolytica/E. dispar. A pesquisa de coproantígenos e a reação em cadeia da polimerase (PCR) têm sido utilizadas para diferenciação desses protozoários em amostras fecais. No entanto, estudos mais aprofundados são necessários para maior compreensão sobre a relação parasita/hospedeiro, a proteômica e a genômica do protozoário, o desenvolvimento de vacinas e a real prevalência dessa infecção no Brasil e no mundo.

10.1590/s1676-24442008000400004

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Seroprevalence of Chagas disease among blood donors in the State of Bahia, Brazil

Mitermayer Galvão dos Reis Diego Lopes Paim Miranda Gilmar Ribeiro Fernanda Cardoso Lanza Fred Luciano Neves Santos

Chagas Disease

Seroprevalence

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Impedimetric immunosensor for rapid and simultaneous detection of chagas and visceral leishmaniasis for point of care diagnosis

Biosensors and Bioelectronics (2020)

Taís Aparecida Reis Cordeiro Helen Rodrigues Martins Diego Leoni Franco Fred Luciano Neves Santos Paola Alejandra Fiorani Celedón

Chagas Disease

10.1016/j.bios.2020.112573

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Infection by Strongyloides stercoralis in immigrants with Chagas disease: evaluation of eosinophilia as screening method in primary care

Tropical Medicine & International Health (2019)

Eva Dopico Yolanda Rando Matos L. Solsona Jesús Almeda Fred Luciano Neves Santos

To evaluate co-infection of Strongyloides stercoralis and Trypanosoma cruzi and to assess eosinophilia as a screening test for the detection of S. stercoralis infection in patients with Chagas disease (CD).A retrospective diagnostic validation study was performed on serum samples from primary care patients diagnosed with CD in the southern Barcelona metropolitan area. All samples with eosinophilia (n = 87) and a random sample of non-eosinophilic sera (n = 180) were selected. Diagnosis of CD was based on positive serology by means of two tests: ORTHO® T. cruzi ELISA test, and BIO-FLASH® Chagas or Bioelisa CHAGAS. SCIMEDX ELISA STRONGY-96 was used to diagnose strongyloidiasis.Strongyloides stercoralis serology was positive in 15% of patients of whom 95% showed eosinophilia, vs. 21% of those with negative serology (P < 0.001), with differences in the mean eosinophil count (0.49 vs. 0.27 × 109 /l). Only 1.1% of patients with CD but without eosinophilia presented positive serology for S. stercoralis, whereas 44% of patients with CD and eosinophilia did (P < 0.001). Sensitivity and specificity values for eosinophilia were thus 95% and 79%, respectively. PPV was 42.5% and NPV, 98.9%.The prevalence of co-infection by T. cruzi and S. stercoralis is not negligible and has probably been underestimated for years in many areas, due to frequently subclinical infections. Therefore, serology seems mandatory for these patients and the use of eosinophilia as initial screening could facilitate the task, decreasing the number of analyses to be performed.Evaluer la coinfection par Strongyloides stercoralis et Trypanosoma cruzi et évaluer éosinophilie comme un test de dépistage pour la détection de l’infection à S. stercoralis chez les patients atteints de la maladie de Chagas (MC). MÉTHODES: Une étude de validation diagnostique rétrospective a été réalisée sur des échantillons de sérum de patients de soins primaires diagnostiqués avec la MC dans la région métropolitaine du sud de Barcelone. Tous les échantillons avec éosinophilie (n = 87) et un échantillon aléatoire de sérums non éosinophiliques (n = 180) ont été sélectionnés. Le diagnostic de la MC était basé sur une sérologie positive au moyen de deux tests: le test ELISA ORTHO® T. cruzi et le test BIO-FLASH® Chagas ou Bioelisa CHAGAS. SCIMEDX ELISA STRONGY-96 a été utilisé pour diagnostiquer la strongyloïdose. RÉSULTATS: La sérologie de S. stercoralis était positive chez 15% des patients dont 95% présentaient une éosinophilie, contre 21% de ceux avec une sérologie négative (P <0,001), avec des différences dans le taux moyen d'éosinophiles (0,49 contre 0,27 × 109 /L). Seuls 1,1% des patients avec la MC mais sans éosinophilie présentaient une sérologie positive pour S. stercoralis ; contrairement à 44% des patients atteints de la MC avec une éosinophilie (p <0,001). Les valeurs de sensibilité et de spécificité pour l'éosinophilie étaient ainsi respectivement de 95% et 79%. La VPP était de 42,5% et la VPN, 98,9%.La prévalence de la coinfection par T. cruzi et S. stercoralis n'est pas négligeable et a probablement été sous-estimée depuis des années dans de nombreuses régions, en raison d'infections fréquemment infracliniques. Par conséquent, la sérologie semble obligatoire pour ces patients et l'utilisation de l'éosinophilie comme dépistage initial pourrait faciliter la tâche, diminuant le nombre d'analyses à effectuer.

Strongyloides stercoralis

Strongyloidiasis

Chagas Disease

Strongyloides

10.1111/tmi.13363

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PREVALÊNCIA DE ENTEROPARASITOSESEM CRIANÇAS DO SERTÃO BAIANO

Revista de Patologia Tropical / Journal of Tropical Pathology (2007)

Genario Oliveira Santos-Júnior Maiara Macêdo Silva Fred Luciano Neves Santos

Neste estudo, a presença de diversos enteroparasitos diagnosticada no período de junho a outubro de 2001, em amostras fecais de 410 crianças de 0 a 6 anos de idade residentes na região rural de Ipirá, sertão baiano, foi associada a diversas condições socioeconômicas e de higiene domiciliar. Verificou-se que 290 apresentavam ovos e/ou cistos de enteroparasitos. Entre estas, foi observada a prevalência de 48,3% para Ascaris lumbricoides e Giardia duodenalis, 6,9% para Ancilostomídeos e Enterobius vermicularis, 10,3% para Trichuris trichiura, 17,2% para Entamoeba coli e 3,4% para Iodamoeba butschlii. A análise dos questionários revelou que 96% das crianças têm o hábito de defecar no peridomicílio e 62% não possuem sistema domiciliar de abastecimento de água.

Entamoeba coli

Trichuris trichiura

10.5216/rpt.v35i3.1884

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Assessment of Cross-Reactivity of Chimeric Trypanosoma cruzi Antigens with Crithidia sp. LVH-60A: Implications for Accurate Diagnostics

Diagnostics (2023)

Emily Ferreira dos Santos Ramona Tavares Daltro Carlos Gustavo Régis-Silva Tycha Bianca Sabaini Pavan Fabrícia Alvisi de Oliveira

This study focuses on developing accurate immunoassays for diagnosing Chagas disease (CD), a challenging task due to antigenic similarities between Trypanosoma cruzi and other parasites, leading to cross-reactivity. To address this challenge, chimeric recombinant T. cruzi antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) were synthesized to enhance specificity and reduce cross-reactivity in tests. While these antigens showed minimal cross-reactivity with leishmaniasis, their performance with other trypanosomatid infections was unclear. This study aimed to assess the diagnostic potential of these IBMP antigens for detecting CD in patients with Crithidia sp. LVH-60A, a parasite linked to visceral leishmaniasis-like symptoms in Brazil. This study involved seven Crithidia sp. LVH-60A patients and three Leishmania infantum patients. The results indicated that these IBMP antigens displayed 100% sensitivity, with specificity ranging from 87.5% to 100%, and accuracy values between 90% and 100%. No cross-reactivity was observed with Crithidia sp. LVH-60A, and only one L. infantum-positive sample showed limited cross-reactivity with IBMP-8.1. This study suggests that IBMP antigens offer promising diagnostic performance, with minimal cross-reactivity in regions where T. cruzi and other trypanosomatids are prevalent. However, further research with a larger number of Crithidia sp. LVH-60A-positive samples is needed to comprehensively evaluate antigen cross-reactivity.

Crithidia

Chagas Disease

Reactivity

Cross-reactivity

Kinetoplastida

10.3390/diagnostics13223470

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Citations (4)