Caracterização morfológica e morfométrica de estágios larvares de Strongyloides spp, ancilostomídeos e Angiostrongylus spp: subsídios para identificação em amostras ambientais / Morphological and morphometric characterization of larval stages of Strongyloides spp, hookworms and Angiostrongylus spp: subsidies for identification in environmental samples

A identificação precisa de nematódeos de interesse médico-veterinário em amostras de solo ou alimentos é uma ação complexa, devido à grande diversidade de nematódeos no ambiente. O objetivo do estudo foi realizar a caracterização morfológica e morfométrica de diferentes estágios larvários de ancilostomídeos, Strongyloides stercoralis, Strongyloides venezuelensis, Angiostrongylus cantonensis e Angiostrongylus costaricensis, e desenvolver um estudo de similaridade entre espécies do mesmo gênero, a fim de orientar o diagnóstico diferencial com os nematódeos ambientais. As larvas foram fixadas e diversos parâmetros corporais foram mensurados, para os quais foi realizada estatística descritiva e estudo de similaridade. Os resultados médios das larvas padrões foram compatíveis com os descritos para as espécies, com variabilidade em alguns parâmetros. S. stercoralis e S. venezuelensis demonstraram similaridade de 59% para L1 e 79% para L3, com maior diferenciação entre os grupos em relação à extremidade anterior e ao primórdio genital. No pool de larvas de ancilostomídeos, verificou-se uma grande variação nos parâmetros avaliados, especialmente quanto ao comprimento total do corpo. A. cantonensis e A. costaricensis apresentaram 48% de similaridade entre L1 e 76% para L3. Por meio da análise morfométrica e de similaridade verificou-se a possibilidade do aprimoramento do diagnóstico diferencial de nematódeos de origem ambiental. (AU)

Due to the enormous diversity of nematodes in the environment, identifying nematodes of medical and veterinary significance within soil or food samples can be challenging. To facilitate the differential diagnosis with environmental nematodes, this study aimed morphologically and morphometrically characterize various larval stages of hookworms, Strongyloides stercoralis, Strongyloides venezuelensis, Angiostrongylus cantonensi and Angiostrongylus costaricensis. Additionally, a similarity study was conducted among species within the same genus. The larvae were fixated and several body parameters were measured for the analysis, which included a comparison using descriptive statistics. Despite some parameter fluctuation, the average results for standard larvae were consistent with those of the respective species as a whole. The similarity between S. stercoralis and S. venezuelensis was 59% for L1 and 79% for L3, with more pronounced differences observed in the anterior extremity and the genital primordium. The examined parameters exhibited significant variation among the pool of hookworm larvae, particularly concerning the total length of the body. The similarities between A. cantonensis and A. costaricensis larvae ranged from 48% for L1 to 76% for L3. Analyses of morphometric and similarity data provided support for the potential improvement of differentiation between nematodes with environmental origins. This research contributes to enhancing the accuracy of identifying medically and veterinary relevant nematodes present in soil. (AU)

Perforación cecal por angiostrongiliasis en un adulto mayor / Cecal perforation due to angiostrongyliasis in an elderly patient

La angiostrongiliasis abdominal es una enfermedad parasitaria causada por el género Angiostrongylus costaricensis, un nematodo que infecta a los humanos a través de las secreciones de caracoles o babosas, sus huéspedes definitivos. Costa Rica es el país que se considera más endémico, se ha evidenciado en distintas revisiones que la mayoría de los casos se presentan en niños y personas del sexo masculino. Presentación del caso. Se trata de una mujer de 74 años, que consultó por dolor abdominal agudo, de cuatro días de evolución, acompañado de náuseas, vómitos e hiporexia. Los exámenes de laboratorio reportaron leucocitosis leve y examen general de orina negativo. La ultrasonografía abdominal reportó una masa sólida, heterogénea, mal circunscrita en flanco derecho, esto llevó a la sospecha de una apendicitis aguda. Intervención terapéutica. Se realizó una laparotomía exploradora, con la extirpación de una tumoración de colon perforado que abarcaba desde el ciego hasta el tercio proximal de colon ascendente, además, se realizó una anastomosis de íleo transversa, sin mayor complicación. Evolución clínica. Se manejó con antibióticos y analgésicos, fue dada de alta a los nueve días posteriores al procedimiento, sin complicaciones menores. La biopsia reportó huevos de parásitos consistentes con Angiostrongylus sp

bdominal angiostrongyliasis is a parasitic disease caused by the genus Angiostrongylus costaricensis, a nematode that infects humans through the secretions of snails or slugs, its definitive hosts. Costa Rica is considered the most endemic country, and it has been shown in different reviews that most cases occur in children and males. Case presentation. The patient was a 74-year-old woman who consulted for acute abdominal pain, with four days of evolution, accompanied by nausea, vomiting, and hyporexia. Laboratory tests reported mild leukocytosis and a negative general urine test. Abdominal ultrasonography reported a solid heterogeneous mass, poorly circumscribed in the right lateral abdomen, which led to the suspicion of acute appendicitis. Treatment. An exploratory laparotomy was performed, with the removal of a perforated colon tumor that spanned from the cecum to the proximal third of the ascending colon, in addition, a transverse ileum anastomosis was performed, without further complication. Outcome. She was managed with antibiotics and analgesics and was discharged nine days after the procedure, without complications. The biopsy showed parasite eggs consistent with Angiostrongylus sp

Morphological and molecular diagnosis of diseases of free-ranging crab-eating foxes (Cerdocyon thous) / [Diagnóstico morfológico e molecular de doenças de cachorro-do-mato (Cerdocyon thous) de vida livre]

The aim of this study was to investigate the occurrence of diseases in free-ranging wild canids that were roadkill on highways in the State of Espírito Santo, Brazil. PCR tests were performed for the detection of Brucella sp., Babesia sp., Rangelia sp., and Hepatozoon sp. in the spleen. Morphological evaluation and identification of parasites was performed in the liver and lung. Twenty specimens of C. thous were necropsied at the Animal Pathology Sector of the Veterinary Hospital of the Universidade Federal do Espírito Santo. Tissue samples were processed for histopathological examination and polymerase chain reaction (PCR) analysis. There was no PCR amplification of genomic DNA sequences of Brucella sp., Babesia sp., Rangelia sp., and Hepatozoon sp. using DNA extracted from the spleen as template. Histologically, lesions associated with parasitism by Platynosomum sp. and Angiostrongylus sp. were observed in the liver and lung, respectively. This is the first report of Platynosomum sp. and Angiostrongylus sp. parasitism in C. thous in the state of Espírito Santo, Brazil. Therefore, this study demonstrated parasitism of crab-eating foxes by Platynosomum sp. and Angiostrongylus sp. Importantly, no evidence of infection with Brucella sp., Babesia sp., Rangelia sp., and Hepatozoon sp. was obtained by PCR analysis.(AU)

O objetivo deste estudo foi investigar a ocorrência de doenças em canídeos silvestres de vida livre que foram atropelados em rodovias no estado do Espírito Santo, Brasil. Testes de PCR foram realizados para a detecção de Brucella sp., Babesia sp., Rangelia sp. e Hepatozoon sp. no baço. A avaliação morfológica e a identificação de parasitas foram realizadaa no fígado e no pulmão. Vinte espécimes de C. thous foram necropsiados no Setor de Patologia Animal do Hospital Veterinário da Universidade Federal do Espírito Santo. Amostras de tecido foram processadas para exame histopatológico e análise de reação em cadeia da polimerase (PCR). Não houve amplificação por PCR das sequências de DNA genômico de Brucella sp., Babesia sp., Rangelia sp. e Hepatozoon sp. usando-se DNA extraído do baço como modelo. Histologicamente, lesões associadas ao parasitismo por Platynosomum sp. e Angiostrongylus sp. foram observadas no fígado e no pulmão, respectivamente. Este é o primeiro relato de Platynosomum sp. e Angiostrongylus sp. parasitismo em C. thous no estado do Espírito Santo, Brasil. Portanto, este estudo demonstrou parasitismo de cachorro-do-mato por Platynosomum sp. e Angiostrongylus sp. É importante detacar que não há evidências de infecção por Brucella sp., Babesia sp., Rangelia sp. e Hepatozoon sp. por análise de PCR.(AU)

Achatina fulica (Gastropoda: Pulmonata): Occurrence, environmental aspects and presence of nematodes in Sergipe, Brazil / Achatina fulica (Gastropoda: Pulmonata): ocorrencia, aspectos ambientais e presença de nematódeos em Sergipe, Brasil

Abstract The objective of this study was to identify the occurrence of Achatina fulica in the Great Aracaju-SE Territory. This research was developed during the months of June 2016 to May 2017. The plots methodology was used for the monthly collections, following the collection time of 20 minutes per area. The mollusks were measured and soon afterwards the parasitological analysis of the mucus and faeces was performed. Molecular identification was performed to evaluate the possible presence of Angiostrongylus sp. We observed that the occurrence of A. fulica was more representative in urban areas, especially in vacant lots with the presence of litter and decomposing materials. In the specimens of A. fulica examined were male and female nematodes of the genus Rhabditis, in the research municipalities, except in Barra dos Coqueiros. No parasites of the genus Angiostrongylus were found in the mollusks examined. The influence of the presence of litter on the plots associated with the frequency of A. fulica was statistically significant. There was a correlation between the influence of rainfall and the frequency of A. fulica. A significant relationship between moisture and frequency and nematode positivity was identified. It was also observed that the larger the mollusk, the greater the chances of being infected by nematodes. Scientific knowledge about the biology of the A. fulica species associated with human intervention such as the maintenance of land and adequate sanitary measures may be important factors for a better control of this invasive mollusk.

Resumo O objetivo deste estudo foi verificar a ocorrência de A. fulica no território da Grande Aracaju, Sergipe, avaliando a infecção destes moluscos por nematódeos, a influência das condições climáticas e das características do ambiente. Esta pesquisa foi desenvolvida durante os meses de junho de 2016 a maio de 2017. Foi utilizada a metodologia de parcelas para as coletas mensais de 20 min por área, um total de 15 parcelas distribuídas em 5 municípios. Os moluscos foram mensurados e logo em seguida realizada a análise parasitológica do muco e fezes. Foi realizada a identificação molecular para avaliar a possível presença de Angiostrongylus sp. Observamos que a ocorrência de A. fulica foi mais representativa em áreas urbanas, sobretudo em terrenos baldios com a presença de lixo e materiais em decomposição. Nos exemplares de A. fulica examinados foram encontrados nematódeos do gênero Rhabditis, nos municípios da pesquisa, exceto em Barra dos Coqueiros. Não foram encontrados parasitos do gênero Angiostrongylus nos moluscos examinados. A influência da presença de lixo nas parcelas associado à frequência da A. fulica mostrou-se estatisticamente significativa. Houve correlação entre a influência da chuva e a frequência de A. fulica. Foi identificada uma relação significativa entre a umidade e a frequência e a positividade para nematódeos. Foi também observado que quanto maior o molusco, maiores são as chances deste apresentar nematódeos. O conhecimento científico a respeito da biologia da espécie A. fulica associado à intervenção humana como, a manutenção de terrenos e medidas sanitárias adequadas podem ser fatores importantes para um controle malacológico mais adequado para esta espécie invasora.

Abdominal angiostrongyliasis, report of two cases and analysis of published reports from Colombia / Angiostrongiliasis abdominal, reporte de dos casos y análisis de los casos publicados en Colombia

Abdominal angiostrongyliasis is a parasitic zoonosis, endemic in the American continent. Its etiological agent is Angiostrongylus costaricensis, a nematode whose definitive hosts are rats and other rodents and the intermediate hosts, slugs. Mammals acquire the infection by consuming vegetables contaminated with L3 larvae. The disease shows a heterogeneous clinical spectrum and given its low incidence its diagnosis is a great challenge. In Colombia, the first case was reported in 1979 and until 1998, only five additional cases have been reported. However, in the last two decades, no new cases were reported. Here we discuss two cases of children from Huila and Caquetá departments who developed the disease. Both cases required long in-patient care and multiple surgical interventions. The diagnosis was achieved by histopathological observation of parasitic elements inside the mesenteric arteries. One of the children died while the other fully recovered. We discuss the epidemiology, pathogenic cycle, clinical presentation, diagnosis, and prevention strategies of this disease paying particular attention to our patients' features and the Colombian context.

La angiostrongiloidiasis abdominal es una zoonosis parasitaria endémica en el continente americano. Su agente etiológico es el nematodo Angiostrongylus costaricensis, cuyos huéspedes definitivos son los roedores y, los intermediarios, los caracoles y las babosas, por lo que se adquiere al consumir vegetales contaminados con larvas en estadio 3. La presentación clínica es muy variada y, dada su rareza, su diagnóstico es un desafío. En Colombia el primer caso se reportó en 1979 y, desde entonces hasta 1998, se han informado cinco casos más, aunque en las últimas dos décadas no se había reportado ningún caso. Se describen aquí dos casos de angiostrongiloidiasis en niños provenientes de los departamentos de Huila y Caquetá que requirieron una larga hospitalización y múltiples intervenciones quirúrgicas. El diagnóstico se logró al observar en los especímenes quirúrgicos larvas and huevos cuya morfología sugería una infección por nematodos; uno de los pacientes murió y el otro se recuperó satisfactoriamente. Se discuten la epidemiología, la patogenia, la presentación clínica, el diagnóstico y las estrategias de prevención de esta parasitosis, con énfasis en las características particulares de los casos descritos y en el contexto colombiano.

Angiostrongylus minasensis n. sp.: new species found parasitizing coatis (Nasua nasua) in an urban protected area in Brazil / Angiostrongylus minasensis n. sp.: nova espécie encontrada parasitando quatis (Nasua nasua) em área de proteção urbana no Brasil

Abstract Currently, there are 21 species of Angiostrongylus that parasitize the pulmonary or mesenteric arteries of wild and domestic rodents, felids, canids and human. Species of Angiostrongylus have cosmopolitan distribution covering tropical, subtropical and temperate regions. The procyonid Nasua nasua (coati) is a reservoir host for a wide variety of parasites that may be harmful to its populations or may contain etiological agents with zoonotic potential. In urban areas, coatis are usually found in close association with humans and domestic animals. We morphologically and molecularly characterized a new species of Angiostrongylus found in N. nasua in a protected area within Belo Horizonte, Brazil. The new species of Angiostrongylus differs from other species of the same genus in terms of the length and bifurcation level of the lateral and ventral rays, the length of spicules and female tail morphology. Molecular phylogenetic results based on the mitochondrial cytochrome c oxidase subunit 1 gene suggest that the newly identified species belongs to a genetic lineage that is separate from other species of Angiostrongylus. This new species was collected from the mesenteric arteries of N. nasua. It was named Angiostrongylus minasensis n. sp..

Resumo Existem 21 espécies de Angiostrongylus que parasitam as artérias pulmonares ou mesentéricas de roedores silvestres e domésticos, felídeos, canídeos e homem. Espécies de Angiostrongylus têm uma distribuição cosmopolita que abrange regiões tropicais, subtropicais e temperadas. O procionídeo Nasua nasua (quati) é hospedeiro de vários parasitos que podem ser prejudiciais para suas populações ou conter agentes etiológicos com potencial zoonótico. Nas áreas urbanas, os quatis podem ser encontrados em estreita associação com seres humanos e animais domésticos. Nós caracterizamos morfológica e molecularmente uma nova espécie de Angiostrongylus encontrada em N. nasua de uma área protegida na cidade de Belo Horizonte, Brasil. A nova espécie de Angiostrongylus difere de outras espécies do mesmo gênero pelo comprimento e nível de bifurcação dos raios lateral e ventral, o comprimento dos espículos e a morfologia da cauda da fêmea. Resultados moleculares e filogenéticos baseados no gene mitocondrial citocromo c oxidase subunidade 1 indicam que a espécie recém-identificada pertence a uma linhagem genética separada de outras espécies de Angiostrongylus. O presente relato descreve uma nova espécie de Angistrongylus coletada das artérias mesentéricas de N. nasua, denominada Angiostrongylus minasensis n. sp..

Gastropods as intermediate hosts of Angiostrongylus spp. in the Americas: bioecological characteristics and geographical distribution

BACKGROUND Intermediate hosts are key organisms in maintaining parasite life cycles, because they can act as amplifiers in the transmission from natural reservoirs to humans. One of the most important groups of intermediate hosts for zoonotic nematode infections are gastropods,slugs and snails. These are essential organisms in the larval development of Angiostrongylus species. OBJECTIVES The objective of this paper is to review reports of Angiostrongylus spp. in naturally infected gastropods from the Americas, taking into account the diagnostic methods used in their identification, to be able to provide more accurate list of their intermediate hosts. We also discuss the factors that aid the dispersion of Angiostrongylus spp. in the Americas. METHODS This study reviews scientific publications and book sections on Angiostrongylus spp. in the Americas, including original works assessing larvae of Angiostrongylus in intermediate hosts. The eligible reports were classified accordingly to their geographical location, year of first record, and the larvae identification methodologies used. Digital repositories were used for the search. The bioecological characteristics of the main intermediate hosts are summarised. FINDINGS A total of 29 gastropod species that are naturally infected with Angiostrongylus spp. have been reported as intermediate hosts, 16 of which are land snails, two are freshwater snails, and 11 land slugs. MAIN CONCLUSIONS This study highlights the importance of integrative studies, analysing both the etiological agent and its transmission dynamic in the environment, the biological and ecological characteristics of the hosts, and the impact on host populations. It is necessary to increase interdisciplinary studies to determine the potential epidemiological health risk of angiostrongyliasis in the Americas, and thus be able to establish prevention, monitoring and contingency strategies in the region.

Abdominal angiostrongyliasis can be diagnosed with a immunochromatographic rapid test with recombinant galactin from Angiostrongylus cantonensis

Angiostrongylus costaricensis is the causative agent of abdominal angiostrongyliasis, a zoonotic infection that may produce severe eosinophilic enterocolitis or hepatitis in humans. Parasites are usually not released in stools and serology has an important role in diagnosis. Since cross-reactivity is demonstrated between A. costaricensis and another metastrongylid worm, A. cantonensis, we tested heterologous recombinant galectin as a probe in an immunochromatographic rapid diagnostic test (ICT-RDT) for detection of anti-A. costaricensis antibodies. Almost all (11/12) positive control sera from A. costaricensis infected patients were positive at ICT RDT. These are preliminary indications that r-galectin ICT-RDT is useful for diagnosing A. costaricensis infection.

New approaches to studying morphological details of intramolluscan stages of Angiostrongylus vasorum / Novas abordagens para estudo morfológico dos estágios intramoluscos de Angiostrongylus vasorum

Abstract Angiostrongylus vasorum is a pulmonary artery parasite of domestic and wild canid. On molluscs, intermediate host, first stage larvae (L1) are found after the first day of infection, in the 8th L2 and in the 30 th L3. It was evaluated L1, L2 and L3 recovered by Baermann technique from Achatina fulica infected with 1000 L1. Fifty larvae/stage were incubated with antibodies anti-β-tubulin, anti-α-tubulin, anti- α-actin, anti-β-actin and anti-collagen, and then with Alexa 633. Fifty larvae/stage were observed with picrosirius red and Oil Red O. It was also observed in the anterior region of L1 the beginning of the chitinous stems development, in the initial portion of the intestine and genital primordium. In L2 anterior region, the papillae, chitinous canes juxtaposed to the mouth and intestines bigger than L1. The L3 musculature is well defined, next to the chitinous stems, there are two round distally arranged from each other. It was observed the whole extension of the intestine genital primordium and intense cellularity in the L3 distal portion. With the picrosirius red the L1, L2 and L3 musculature could be observed, as the nerve ganglia on L3. Oil Red O revealed that L1, L2 and L3 store energy on lipid droplets.

Resumo Angiostrongylus vasorum é um parasito de artérias pulmonares dos canídeos domésticos e silvestres. Nos moluscos, hospedeiros intermediários, encontram-se no primeiro dia após a infecção, larvas de primeiro estágio (L1), ao 8° L2 e ao 30° L3. Avaliou-se L1, L2 e L3 recuperadas pela técnica de Baermann de Achatina fulica infectada com 1.000 L1. Incubou-se 50 larvas/estádio com anticorpos anti-β-tubulina, anti-α-tubulina, anti-β-actina e anti-colágeno e, em seguida, com anticorpo Alexa 633. Observaram-se também 50 larvas/estádio com picrosirius red e Oil Red O, na região anterior da L1, o início do desenvolvimento de hastes quitinosas, a porção inicial do intestino e o primórdio genital. Na região anterior de L2, papilas, bastões quitinosos justapostos à boca e ao intestino maior que em L1. A musculatura de L3 é bem desenvolvida, próximo às hastes quitinosas, há duas estruturas redondas dispostas distalmente uma da outra. Observaram-se também toda a extensão do intestino, o primórdio genital e a intensa celularidade na porção distal da L3. Com o picrosirius red observou-se a musculatura de L1, L2 e L3, assim como, gânglios nervosos na L3. Oil Red O revelou que L1, L2 e L3 armazenam energia em gotículas lipídicas.

Dexamethasone Downregulates Expressions of 14-3-3β and γ-Isoforms in Mice with Eosinophilic Meningitis Caused by Angiostrongylus cantonensis Infection

Steroids are commonly used in patients with eosinophilic meningitis caused by A. cantonensis infections. The mechanism steroids act on eosinophilic meningitis remains unclear. In this mouse experiments, expressions of 14-3-3 isoform β and γ proteins significantly increased in the CSF 2–3 weeks after the infection, but not increasedin the dexamethasone-treated group. Expression of 14-3-3 β, γ, ɛ, and θ isoforms increased in brain meninges over the 3-week period after infection and decreased due to dexamethasone treatment. In conclusion, administration of dexamethasone in mice with eosinophilic meningitis decreased expressions of 14-3-3 isoform proteins in the CSF and in brain meninges.

Diagnóstico molecular de larvas de Angiostrongylus spp. recuperadas de gastrópodes / Molecular diagnosis of Angiostrongylus spp. recovered from gastropods

Gastrópodes continentais atuam como hospedeiros intermediários de nematódeos de interesse para a saúde humana e animal, como Angiostrongylus spp. e outros pertencentes à superfamília Metastrongyloidea. O procedimento de digestão artificial é comumente utilizado para recuperar larvas de nematódeos em moluscos. Entretanto, essas formas imaturas não apresentam desenvolvidos os caracteres morfológicos necessários à sua identificação taxonômica. Como o produto da digestão artificial é ácido e contém restos de tecido do molusco, também surgem dificuldades para realizar o diagnóstico molecular destas larvas. Estudos pilotos mostraram ineficiência no diagnóstico molecular devido a variações na qualidade da amostra, baixa concentração de DNA e baixa eficiência nas Reações em Cadeia da Polimerase (PCR). O objetivo deste trabalho foi aprimorar o diagnóstico molecular de larvas de Angiostrongylus spp. obtidas de moluscos. Assim, inicialmente, foi padronizado um método de preparo das larvas (triagem das larvas com micropipeta, somado ao ajuste do pH com PBS 1X ). A partir destas amostras padronizadas quanto ao método de preparo, foram testados métodos de extração de DNA e diferentes iniciadores para a região do Citocromo c Oxidase subunidade I (COI). Foram utilizadas larvas L3 de Angiostrongylus cantonensis, A. costaricensis e A. vasorum provenientes de ciclos mantidos em laboratório.

Amostras do campo de Aelurostrongylus abstrusus também foram utilizadas para comparação. A importância do preparo da amostra foi testada através de reações de PCR realizadas em condições idênticas, com amostras padronizadas e não padronizadas quanto ao preparo. Quanto aos testes de extração, após a realização de pilotos com diferentes protocolos, foram selecionados para testes comparativos, até a etapa de sequenciamento, dois protocolos com choque térmico e um utilizando kit comercial. Estes foram avaliados quanto à quantidade de DNA, eficiência da amplificação, tempo de realização e qualidade da sequência. Em uma terceira etapa foram testados três diferentes iniciadores para o COI. Os resultados demonstraram que após uma lavagem com PBS o produto da digestão artificial torna-se neutro (pH 7,29 ± 0,13) e que estas amostras, devidamente triadas, apresentam taxa de amplificação 60% maior. Este passo mostrou-se essencial para o sucesso das demais etapas. As amostras que foram submetidas à extração de DNA com os três protocolos selecionados resultaram em um produto que permitiu a amplificação do fragmento do COI nas reações de PCR, apesar das baixas concentrações de DNA, tendo sido possível também o diagnóstico molecular, por sequenciamento de Sanger, de 100% dessas amostras.

Os protocolos com choque térmico apresentaram menor tempo de execução, custo e geração de resíduo químico. Os três iniciadores testados amplificaram com eficiência a região-alvo, viabilizando a identificação de Angiostrongylus spp. por sequenciamento. Os diferentes métodos de extração e iniciadores testados representam diferentes possibilidades para o diagnóstico de larvas de Angiostrongylus spp. e seu uso deverá levar em conta os recursos disponíveis (tempo e dinheiro) e o objetivo do estudo (diagnóstico ou pesquisa). A disponibilização de um protocolo eficiente e a possibilidade de redução dos custos no diagnóstico dos nematódeos associados a moluscos contribuem para incentivar as pesquisas na área e viabilizar estudos de vigilância epidemiológica e controle das angiostrongilíases. (AU)

Angiostrongylus spp. in the Americas: geographical and chronological distribution of definitive hosts versus disease reports

BACKGROUND Angiostrongyliasis is an infection caused by nematode worms of the genus Angiostrongylus. The adult worms inhabit the pulmonary arteries, heart, bronchioles of the lung, or mesenteric arteries of the caecum of definitive host. Of a total of 23 species of Angiostrongylus cited worldwide, only nine were registered in the American Continent. Two species, A. cantonensis and A. costaricensis, are considered zoonoses when the larvae accidentally parasitise man. OBJECTIVES In the present study, geographical and chronological distribution of definitive hosts of Angiostrongylus in the Americas is analysed in order to observe their relationship with disease reports. Moreover, the role of different definitive hosts as sentinels and dispersers of infective stages is discussed. METHODS The study area includes the Americas. First records of Angiostrongylus spp. in definitive or accidental hosts were compiled from the literature. Data were included in tables and figures and were matched to geographic information systems (GIS). FINDINGS Most geographical records of Angiostrongylus spp. both for definitive and accidental hosts belong to tropical areas, mainly equatorial zone. In relation to those species of human health importance, as A. cantonensis and A. costaricensis, most disease cases indicate a coincidence between the finding of definitive host and disease record. However, in some geographic site there are gaps between report of definitive host and disease record. In many areas, human populations have invaded natural environments and their socioeconomic conditions do not allow adequate medical care. MAIN CONCLUSIONS Consequently, many cases for angiostrongyliasis could have gone unreported or unrecognised throughout history and in the nowadays. Moreover, the population expansion and the climatic changes invite to make broader and more complete range of observation on the species that involve possible epidemiological risks. This paper integrates and shows the current distribution of Angiostrongylus species in America, being this information very relevant for establishing prevention, monitoring and contingency strategies in the region.

Características de angiostrongilosis addominal en Honduras / Characteristics of abdominal angiostrongylosis in Honduras

La angiostrongilosis abdominal es una patología descrita en Honduras desde 1972, se caracteriza por abdomen agudo con eosinofilia, existen pocos datos publicados en el país. Objetivo: caracterizar aspectos generales de la angiostrongilosis abdominal y la distribución de los casos estudiados en Honduras Material y métodos: se revisaron publicaciones nacionales e internacionales en las bases de datos: Biblioteca Virtual Salud Honduras, PubMed, SciELO, Google Académico; en inglés y español, con publicaciones desde 1972 hasta 2016, utilizando como descriptores: angiostrongilosis abdominal, angiostrongylus costaricensis en Honduras. Resultados: se encontraron casos publicados en Cortés, Francisco Morazán, Comayagua y El Paraíso, y babosas infectadas en los departamentos mencionados y Olancho. La mayoría de casos son niños, con abdomen agudo, fiebre, hiporexia e irritación peritoneal con leucocitosis y eosinofilia. Hay estudios de serología pero no disponibles en Honduras, el estándar de oro es la biopsia y el tratamiento es quirúrgico. Conclusión: en Honduras existen publicaciones de la existencia de esta zoonosis tanto en humanos como en roedores y los parásitos se han encontrado en babosa. Se considera una enfermedad parasitaria de difícil diagnóstico y prevención, por tanto, existen aspectos que no se conocen, por lo que, se deben realizar estudios serológicos en humanos, búsqueda de parásitos en babosas y roedores, para conocer las áreas afectadas y su distribución geográfica. Palabras clave: An

Susceptibility of Biomphalaria glabrata submitted to concomitant infection with Angiostrongylus costaricensis and Schistosoma mansoni / Suscetibilidade de Biomphalaria glabrata submetida à infecção concomitante com Angiostrongylus costaricensis e Schistosoma mansoni

Abstract The easy adaptation of Angiostrongylus costaricensis, nematode responsible for abdominal angiostrongyliasis to several species of terrestrial and freshwater molluscs and the differences observed in the interactions of trematodes with their intermediate hosts have induced us to study the concomitant infection of Biomphalaria glabrata with Schistosoma mansoni and A. costaricensis. Prior exposure of B. glabrata to A. costaricensis (with an interval of 48 hours), favored the development of S. mansoni, observing higher infection rate, increased release of cercariae and increased survival of molluscs, when compared to molluscs exposed only to S. mansoni. Prior exposure of B. glabrata to A. costaricensis and then to S. mansoni also enabled the development of A. costaricensis since in the ninth week of infection, higher amount of A. costaricensis L3 larvae was recovered (12 larvae / mollusc) while for molluscs exposed only to A. costaricensis, the number of larvae recovered was lower (8 larvae / mollusc). However, pre-exposure of B. glabrata to S. mansoni (with an interval of 24 hours), and subsequently exposure to A. costaricensis proved to be very harmful to B. glabrata, causing extensive mortality of molluscs, reduced pre-patent period to release cercariae and greater recovery of L3 A. costaricensis larvae.

Resumo A facilidade de adaptação do Angiostrongylus costaricensis, nematódeo responsável pela angiostrongiliase abdominal, a diversas espécies de moluscos terrestres e dulciaquícolas e as divergências observadas nas interações dos trematódeos com seus hospedeiros intermediários nos induziu a estudar a infecção concomitante de Biomphalaria glabrata com Schistosoma mansoni e A. costaricensis. A exposição prévia de B. glabrata ao A. costaricensis (com intervalo de 48 horas), favoreceu o desenvolvimento do S. mansoni observando-se elevação da taxa de infecção, maior liberação de cercárias e maior sobrevivência dos moluscos, quando comparado com os moluscos expostos somente ao S. mansoni. A exposição de B. glabrata previamente ao A. costaricensis e posteriormente ao S. mansoni também facilitou o desenvolvimento do A. costaricensis uma vez que na nona semana de infecção foi recuperada maior quantidade de larvas L3 de A. costaricensis, enquanto nos moluscos expostos somente ao A. costaricensis, o número de larvas recuperadas foi menor . Entretanto a pré-exposição de B. glabrata ao S. mansoni (com intervalo de 24 horas), e posteriormente a exposição ao A. costaricensis mostrou-se muito prejudicial à B. glabrata provocando grande mortalidade dos moluscos, redução do período pré-patente para liberação de cercárias e maior recuperação de larvas L3 de A. costaricensis.

Characterisation of the vascular pathology in Sigmodon hispidus (Rodentia: Cricetidae) following experimental infection with Angiostrongylus costaricensis (Nematoda: Metastrongylidae)

BACKGROUND Angiostrongylus costaricensis is a nematode that causes human abdominal angiostrongyliasis, a disease found mainly in Latin American countries and particularly in Brazil and Costa Rica. Its life cycle involves exploitation of both invertebrate and vertebrate hosts. Its natural reservoir is a vertebrate host, the cotton rat Sigmodon hispidus. The adult worms live in the ileo-colic branches of the upper mesenteric artery of S. hispidus, causing periarteritis. However, there is a lack of data on the development of vasculitis in the course of infection. OBJECTIVE To describe the histopathology of vascular lesions in S. hispidus following infection with A. costaricensis. METHODS Twenty-one S. hispidus were euthanised at 30, 50, 90 and 114 days post-infection (dpi), and guts and mesentery (including the cecal artery) were collected. Tissues were fixed in Carson’s Millonig formalin, histologically processed for paraffin embedding, sectioned with a rotary microtome, and stained with hematoxylin-eosin, resorcin-fuchsin, Perls, Sirius Red (pH = 10.2), Congo Red, and Azan trichrome for brightfield microscopy analysis. FINDINGS At 30 and 50 dpi, live eggs and larvae were present inside the vasa vasorum of the cecal artery, leading to eosinophil infiltrates throughout the vessel adventitia and promoting centripetal vasculitis with disruption of the elastic layers. Disease severity increased at 90 and 114 dpi, when many worms had died and the intensity of the vascular lesions was greatest, with intimal alterations, thrombus formation, iron accumulation, and atherosclerosis. CONCLUSION In addition to abdominal angiostrongyliasis, our data suggest that this model could be very useful for autoimune vasculitis and atherosclerosis studies.

Neuronal Apoptosis: Pathological Basis of Behavioral Dysfunctions Induced by Angiostrongylus cantonensis in Rodents Model

Angiostrongylus cantonensis invades the central nervous system (CNS) of humans to induce eosinophilic meningitis and meningoencephalitis and leads to persistent headache, cognitive dysfunction, and ataxic gait. Infected mice (nonpermissive host), admittedly, suffer more serious pathological injuries than rats (permissive host). However, the pathological basis of these manifestations is incompletely elucidated. In this study, the behavioral test, histological and immunohistochemical techniques, and analysis of apoptotic gene expression, especially caspase-3, were conducted. The movement and motor coordination were investigated at week 2 post infection (PI) and week 3 PI in mice and rats, respectively. The cognitive impairs could be found in mice at week 2 PI but not in rats. The plaque-like lesion, perivascular cuffing of inflammatory cells, and dilated vessels within the cerebral cortex and hippocampus were more serious in mice than in rats at week 3 PI. Transcriptomic analysis showed activated extrinsic apoptotic pathway through increased expression of TNFR1 and caspase-8 in mice CNS. Immunohistochemical and double-labeling for NeuN and caspase-3 indicated the dramatically increased expression of caspase-3 in neuron of the cerebral cortex and hippocampus in mice but not in rats. Furthermore, western-blotting results showed high expression of cleaved caspase-3 proteins in mice but relatively low expression in rats. Thus, extrinsic apoptotic pathway participated in neuronal apoptosis might be the pathological basis of distinct behavioral dysfunctions in rodents with A. cantonensis infection. It provides the evidences of a primary molecular mechanism for the behavioral dysfunction and paves the ways to clinical diagnosis and therapy for A. cantonensis infection.

New host, geographic records, and histopathologic studies ofAngiostrongylus spp (Nematoda: Angiostrongylidae) in rodents from Argentina with updated summary of records from rodent hosts and host specificity assessment

To date, 21 species of the genus Angiostrongylus (Nematoda: Angiostrongylidae) have been reported around the world, 15 of which are parasites of rodents. In this study, new host, geographic records, and histopathologic studies of Angiostrongylus spp in sigmodontine rodents from Argentina, with an updated summary of records from rodent hosts and host specificity assessment, are provided. Records of Angiostrongylus costaricensis from Akodon montensis andAngiostrongylus morerai from six new hosts and geographical localities in Argentina are reported. The gross and histopathologic changes in the lungs of the host species due to angiostrongylosis are described. Published records of the genus Angiostrongylus from rodents and patterns of host specificity are presented. Individual Angiostrongylusspecies parasitise between one-19 different host species. The most frequent values of the specificity index (STD) were between 1-5.97. The elevated number of host species (n = 7) of A. morerai with a STD = 1.86 is a reflection of multiple systematic studies of parasites from sigmodontine rodents in the area of Cuenca del Plata, Argentina, showing that an increase in sampling effort can result in new findings. The combination of low host specificity and a wide geographic distribution of Angiostrongylus spp indicates a troubling epidemiological scenario although, as yet, no human cases have been reported.

Development of Lateral Flow Immunoassay for Antigen Detection in Human Angiostrongylus cantonensis Infection

Angiostrongyliasis is difficult to be diagnosed for the reason that no ideal method can be used. Serologic tests require specific equipment and are not always available in poverty-stricken zone and are time-consuming. A lateral flow immunoassay (LFIA) may be useful for angiostrongyliasis control. We established a LFIA for the diagnosis of angiostrongyliasis based on 2 monoclonal antibodies (mAbs) against antigens of Angiostrongylus cantonensis adults. The sensitivity and specificity were 91.1% and 100% in LFIA, while those of commercial ELISA kit was 97.8% and 86.3%, respectively. Youden index was 0.91 in LFIA and 0.84 in commercial ELISA kit. LFIA showed detection limit of 1 ng/ml of A. cantonensis ES antigens. This LFIA was simple, rapid, highly sensitive and specific, which opened an alternative approach for the diagnosis of human angiostrongyliasis.

Estudo da evolução das lesões vasculares presentes na angiostrongilíase abdominal experimental em Sigmodon hispidus (Rodentia: Cricetidae) / Study of the vascular lesions evolution which present in experimentalabdominal angiostrongyliasis in Sigmodon hispidus (Rodentia: Cricetidae)

Introdução: O Angiostrongylus costaricensis é um nematódeo que causa aangiostrongilíase abdominal. O ciclo de vida deste parasita envolve um hospedeiro invertebrado (intermediário) e um hospedeiro vertebrado mamífero (definitivo). Na natureza, um dos principais hospedeiros definitivos deste parasita é o roedor Sigmodon hispidus. O nematódeo instala-se na artéria mesentérica superior do hospedeiro definitivo, causando inicialmente uma periarterite e o sinofílica e posteriormente um trombo. Histopatologicamente, uma tríade de achados fundamentais define esta patologia: massivo infiltrado e o sinofílico; vasculiteeosinofílica e reação granulomatosa. Apesar da importância clínica, pouco se sabe a cerca dessa patologia. Objetivos: Caracterizar as lesões histopatológicas do território vascular e intestinal; acompanhar a dinâmica hematológica periférica e central; avaliar colesterolemia total e a presença de bactérias na lesão de S. hispidusinfectados com A. costaricensis. Material e Métodos: S. hispidus infectados com A. costaricensis foram eutanasiados em 30, 50, 90 e 114 dpi e foram coletados o intestino e mesentério (incluindo a artéria cecal). Os tecidos foram fixados emformalina Millonig de Carson e, histologicamente processados para microscopia de luz ou imunohistoquímica. O sangue também foi coletado através de punção cardíaca ou do plexo braquial e utilizado para realização de hemograma e análise da colesterolemia total e análise microbiológica. A lesão local também foi coletada para análise microbiológica. Resultados e discussão:...

Introduction: Angiostrongylus costaricensis is a roundworm which causes theabdominal angiostrongyliasis. This parasite’s life cycle involves an invertebrate host(intermediary) and a vertebrate host (definitive). In nature, the usual definitive host forthis parasite is the rodent Sigmodon hispidus. Adult worms install in the uppermesenteric artery of the definitive host, causing in the beginning an eosinophilicpolyarteritis and then a thrombus. Histopathologically, a triad of essential findingdefines this pathology as: massive eosinophilic infiltrate; eosinophilic vasculitis andthe granulomatous reaction. Despite the clinical importance, we know just a fewabout this pathology. Objectives: To characterize the histopathological lesions of thevascular and intestinal territories; to follow the peripheral and central hematologicdynamics; to evaluate the total cholesterol and the bacteria presence in the lesion onthe infected S. hispidus by A. costaricensis. Material and Methods: S. hispidusinfected by A. costaricensis were euthanized in 30, 50, 90 and 114 dpi and werecolected the intestine and mesentery (including the cecal artery). Tissues were fixedin Carson’s Millonig formalin and, histopathologically processed to light microscopy orimmunohistochemistry. The blood was also gathered through the cardiac puncture orfrom the brachial plexus and used to the CBC conduction and analysis of totalcholesterol and microbiological analysis. The local lesion was also gathered tomicrobiological analysis. Results and discussion:...