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.

Infection by Angiostrongylus cantonensis in both humans and the snail Achatina (Lissachatina) fulica in the city of Macapá, in the Amazon Region of Brazil

In January and February 2019, a malacological survey was conducted in the area surrounding the residence of a 12-year-old child that had contracted cerebral angiostrongyliasis in the municipality of Macapá, capital of the Amapá State, northern Brazil. The serological examination was positive for Angiostrongylus cantonensis infection, the principal etiological agent of this parasitosis. A sample of 54 molluscs was artificially and individually digested for parasitological analysis, containing 38 specimens of Achatina fulica, nine specimens of Bulimulus tenuissimus and seven specimens of Sarasinula linguaeformis. A. fulica was the most abundant mollusc, and the only species infected with A. cantonensis, as well as presenting co-infections with other nematodes. This is the first report of cerebral angiostrongyliasis in the Amazon Region, and the first record of A. fulica infected with A. cantonensis in Amapá. These findings highlight the potential risks of human angiostrongyliasis, and the need to implement public health measures to control the spread of the disease.

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.

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.

A Case of Ocular Angiostrongyliasis with Molecular Identification of the Species in Vietnam

A 23-year-old female residing in a village of Cao Bang Province, North Vietnam, visited the Hospital of Hanoi Medical University in July 2013. She felt dim eyes and a bulge-sticking pain in her left eye for some days before visiting the hospital. In the hospital, a clinical examination, an eye endoscopy, and an operation were carried out. A nematode specimen was collected from the eye of this patient. The body of this worm was thin and long and measured 22.0x0.3 mm. It was morphologically suggested as an immature female worm of Angiostrongylus cantonensis. By a molecular method using 18S rRNA gene, this nematode was confirmed as A. cantonensis. This is the first molecular study for identification of A. cantonensis in Vietnam.

Eosinophilic meningitis caused by Angiostrongylus cantonensis: an emergent disease in Brazil

Eosinophilic meningitis (EoM) is an acute disease that affects the central nervous system. It is primarily caused by infection with the nematode Angiostrongylus cantonensis. This infection was previously restricted to certain Asian countries and the Pacific Islands, but it was first reported in Brazil in 2007. Since then, intermediate and definitive hosts infected with A. cantonensis have been identified within the urban areas of many states in Brazil, including those in the northern, northeastern, southeastern and southern regions. The goals of this review are to draw the attention of the medical community and health centres to the emergence of EoM in Brazil, to compile information about several aspects of the human infection and mode of transmission and to provide a short protocol of procedures for the diagnosis of this disease.

Angiostrongylus cantonensis: un parásito emergente en Ecuador / Angiostrongylus cantonensis: an emerging parasite in Ecuador

Introducción: en 2008 se notificó por primera vez la presencia de Angiostrongylus cantonensis en Ecuador, así como los primeros casos de una enfermedad emergente causada por sus larvas, la meningitis eosinofilica. Métodos: se realizó una revisión de la literatura básica y actualizada sobre aspectos generales de Angiostrongylus cantonensis en el mundo y particulares en Ecuador, que incluyó los hallazgos parasitológicos, clínicos y malacológicos relacionados con la enfermedad. Resultados: se informan los hallazgos iniciales acerca de la aparición del parásito en Ecuador, así como la amplia distribución geográfica de sus hospederos intermediarios en el territorio nacional. Además, se notifican los brotes de meningitis eosinofilica por Angiostrongylus cantonensis y un caso de angiostrongyliosis ocular, informados oficialmente por el Ministerio de Salud Pública. Conclusiones: Angiostrongylus cantonensis es un parásito emergente en Ecuador, cuyo diagnóstico en la actualidad es clínico y epidemiológico, de ahí la importancia de contar con métodos de laboratorio que lo oriente. Por otra parte, es importante que se promuevan campañas de promoción y prevención de salud que contribuyan a romper la cadena de transmisión de la enfermedad.

Introduction: the presence of Angiostrongylus cantonensis and the first cases of eosinophilic meningitis, an emerging disease caused by its larvae, were first reported in Ecuador in the year 2008. Methods: a review was conducted of the basic and current bibliography on general aspects of Angiostrongylus cantonensis both worldwide and in Ecuador, including parasitological, clinical and malacological findings. Results: initial findings are reported about the emergence of the parasite in Ecuador, as well as the broad geographic distribution of its intermediate hosts in the national territory. Information is also provided about outbreaks of eosinophilic meningitis due to Angiostrongylus cantonensis and a case of ocular angiostrongylosis, based on official reports by the Ministry of Public Health. Conclusions: Angiostrongylus cantonensis is an emerging parasite in Ecuador whose diagnosis is currently based on clinical and epidemiological findings. Hence the importance of developing relevant laboratory methods. On the other hand, it is important to foster health promotion and prevention campaigns aimed at stopping the transmission of the disease.

Molecular diagnosis of eosinophilic meningitis due to Angiostrongylus cantonensis (Nematoda: Metastrongyloidea) by polymerase chain reaction-DNA sequencing of cerebrospinal fluids of patients

Cerebrospinal fluid (CSF) samples from clinically diagnosed patients with detectable Angiostrongylus canto-nensis-specific antibodies (n = 10), patients with clinically suspected cases that tested negative for A. cantonensis-an-tibodies (n = 5) and patients with cerebral gnathostomiasis (n = 2) and neurocysticercosis (n = 2) were examined by a single-step polymerase chain reaction (PCR) method using the AC primers for the 66-kDa native protein gene. The PCR method detected A. cantonensis DNA in CSF samples from four of 10 serologically confirmed angiostrongyliasis cases. The PCR results were negative for the remaining CSF samples. The nucleotide sequences of three positive CSF-PCR samples shared 98.8-99.2% similarity with the reference sequence of A. cantonensis. These results indicate the potential application of this PCR assay with clinical CSF samples for additional support in the confirmation of eosinophilic meningitis due to A. cantonensis.

Ocular angiostrongyliasis: first case report from Jamaica / La angiostrongyliasis ocular: primer caso reportado en Jamaica

A 30-year old female presented with a one-month history of blurred vision in her left eye. Examination revealed a live motile worm in the anterior chamber of the left eye. She also had retinal pigment epithelial disturbance with focal intraretinal haemorrhage. The 19.9 mm worm was surgically removed and identified as Angiostrongylus cantonesis. She was treated with oral mebendazole. Her vision improved from counting fingers in the left eye to 6/36. This is the first documented case of ocular angiostrongyliasis in Jamaica.

Una mujer de 30 años se presentó con una historia de visión borrosa en el ojo izquierdo por un mes. El examen reveló la presencia de un gusano móvil vivo en la cámara anterior de su ojo izquierdo. También presentaba una alteración del epitelio pigmentario de la retina con hemorragia intraretiniana focal. El gusano de 19.9 mm fue extraído quirúrgicamente e identificado como Angiostrongylus cantonesis. La paciente fue tratada con mebendazole oral. Su visión mejoró - pasando de poder contar sólo sus dedos con el ojo izquierdo a una visión de 6/36. Se trata del primer caso de angiostrongyliasis ocular documentado en Jamaica.

Abdominal angiostrongyliasis: report of two cases with different clinical presentations / Angiostrongilíase abdominal: relato de dois casos com diferentes apresentações clínicas

Abdominal angiostrongyliasis is a sporadic infectious disease caused by the nematode Angiostrongylus costaricensis. It usually presents as acute abdomen, secondary to mesenteric ischemia, and pronounced eosinophilia. In some cases its course is insidious and transient, and the diagnosis is suspicious. The disease is confirmed by the detection of A. costaricensis elements in surgical specimen. The treatment is supportive, with avoidance of antihelminthic administration due to a possible erratic migration followed by worsening of the disease. We report two cases, both with intense eosinophilia and serum IgG-ELISA positive to A. costaricensis. The first case presented ileal perforation and was surgically treated. The second one showed hepatic nodules at ultrasound and was only symptomatically treated, evolving to an apparent protracted resolution. These two cases exemplify different clinical forms of the disease, one of them with liver involvement.

A angiostrongilíase abdominal é doença esporádica decorrente da infecção pelo nematódeo Angiostrongylus costaricensis. Costuma manifestar-se como abdome agudo secundário a isquemia mesentérica, além de marcada eosinofilia. Pode também apresentar-se de forma insidiosa e transitória, exigindo alta suspeita clínica para o diagnóstico. A doença é confirmada pela identificação de elementos do A. costaricensis em peças cirúrgicas. O tratamento é apenas de suporte, devendo-se evitar o uso de anti-helmínticos pela possibilidade de migração errática do verme com piora do quadro. Aqui foram apresentados dois casos, ambos com acentuada eosinofilia e ELISA-IgG sérico positivo para A. costaricencis. O primeiro caso cursou com perfuração ileal e foi tratado cirurgicamente. O segundo caso apresentou nódulos hepáticos ao ultrassom e foi tratado sintomaticamente, evoluindo para lenta resolução. Estes dois casos exemplificam diferentes formas de apresentação clínica da doença, uma delas com envolvimento hepático.

Detection of circulating antibody of Parastrongylus cantonensis in sera with eosinophilic meningitis by dot-blot ELISA.

BACKGROUND: Eosinophilic meningitis caused by Parastrongylus cantonensis, the rat lung worm is a major public health problem in Thailand. Humans acquire this parasite by eating raw food containing infective Parastrongyliasis is dificult to make because identification of parasite materials by biopsy or chance finding is rarely possible. OBJECTIVE: Develop alternative approaches of Parastrongylus cantonensis infection employing crude antigen by dot-blot ELISA. MATERIAL AND METHOD: The investigation was carried out between October 2003 and July 2004 in Khon Kaen, which is an endemic area. One hundred thirty two serum samples from several villagers of the present study area were divided into five groups. Group 1 consisted of 30 patients with Cryptococcal meningitis, group 2 were 22 cases of Bacterial meningitis, group 3 were 32 cases of eosinophilic meningitis, group 4 were other parasitic infections (4 from Cysticercosis, 2 from Fascioliasis, 12 from Malaria), and group 5 were 30 negative healthy control. RESULTS: The result demonstrated that 26 cases of eosinophilic meningitis, were positive with Dot-blot ELISA (81.3%). None of the other groups of sample reacted with this antigen. CONCLUSION: The data obtained showed that Dot-blot ELISA has a potential for diagnosis of eosinophilic meningitis caused by Parastrongylus cantonensis.

Individual serological follow-up of patients with suspected or confirmed abdominal angiostrongyliasis

Abdominal angiostrongyliasis (AA) is a zoonotic nematode infection caused by Angiostrongylus costaricensis, with widespread occurrence in the Americas. Although the human infection may be highly prevalent, morbidity is low in Southern Brazil. Confirmed diagnosis is based on finding parasitic structures in pathological examination of biopsies or surgical resections. Serology stands as an important diagnostic tool in the less severe courses of the infection. Our objective is to describe the follow up of humoral reactivity every 2-4 weeks up to one year, in six individuals with confirmed (C) and ten suspected (S) AA. Antibody (IgG) detection was performed by ELISA and resulted in gradually declining curves of reactivity in nine subjects (56 percent) (4C + 5S), that were consistently negative in only three of them (2C + 1S) after 221, 121 and 298 days. Three individuals (2C + 1S) presented with low persistent reacitivity, other two (1C + 1S) were serologically negative from the beginning, but also presenting a declining tendency. The study shows indications that abdominal angiostrongyliasis is usually not a persistent infection: although serological negativation may take many months, IgG reactivity is usually declining along time and serum samples pairing may add valuable information to the diagnostic workout.

Human infection by Angiostrongylus costaricensis in Venezuela: first report of a confirmed case

A proven case of human infection caused by Angiostrongylus costaricensis is reported for the first time in Venezuela. The patient was a 57-year-old female surgically operated because of signs of peritonitis with a palpable mass at the lower right quadrant of the abdomen. WBC count reported 16,600 cells/mm³, with 46 percent eosinophils. The tumoral aspect of ileocolic area and peritoneal lymph nodes prompted the resection of a large area of the terminal ileum, cecum, part of the ascending colon and a small part of the jejunum, where a small lesion was found. The pathology showed thickened areas of the intestinal wall with areas of hemorrhage and a perforation of the cecum. Histology showed intense eosinophil infiltration of the whole intestinal wall, granulomas with giant cells and eosinophils. Some of the granuloma surrounded round or oval eggs with content characterized by a large empty area, cells or embryo in the center, and sometimes nematode larvae. A cross section of an adult nematode worm was observed inside a branch of mesenteric artery. The intestinal affected area, the characteristics of the lesions, the presence of eggs in the submucosa with nematode larvae inside, and the observation of a nematode inside a mesenteric artery, makes sufficient criteria for the diagnosis of an infection by Angiostrongylus costaricensis.

Un caso comprobado de infección humana por Angiostrongylus costaricensis es reportado para la literatura por vez primera en Venezuela. El paciente fue una mujer de 57 años de edad intervenida quirúrgicamente debido a signos de peritonitis, con una masa palpable en la fosa ilíaca derecha del abdomen. El recuento de leucocitos reportó 16.600 células/mm³ con 46 por ciento eosinófilos. El aspecto tumoral del área íleocólica y las adenopatías peritoneales encontradas motivó la resección de un área grande del ileon terminal, ciego, parte del colon ascendente y una pequeña parte del yeyuno donde se encontró una pequeña lesión interpretada como metastásica. La patología mostró áreas engrosadas de la pared intestinal con zonas de hemorragia y perforación del ciego. El estudio histológico mostró una intensa infiltración eosinofílica de toda la pared intestinal, granulomas con células gigantes y eosinófilos. Algunos de los granulomas rodeaban huevos ovales o redondos con un contenido caracterizado por una gran área vacía, células o embriones en el centro, y en algunos casos una larva de nematodo. Un corte transversal de un verme nematodo adulto se observó dentro de una arteria mesentérica. El área intestinal afectada, las características de las lesiones, la presencia de huevos en la submucosa con larvas de nematodo dentro, y la observación de un nematodo dentro de una arteria mesentérica, aportan suficientes criterios para el diagnóstico de una infección por Angiostrongylus costaricensis.

Communicating hydrocephalus as a complication of eosinophilic meningoencephalitis.

The authors reported an adult patient with communicating hydrocephalus in eosinophilic meningoencephalitis. He presented with localized peritonitis and then developed eosinophilic meningoencephalitis. Angiostrongylus cantonensis was the causative agent. This was confirmed by the positive serology test. His consciousness did not recover after supportive treatment. The MRI of the brain showed diffuse enlargement of the ventricular system two weeks after the diagnosis was made. The parameters for hydrocephalus were measured and were compatible with the Gyldensted's criteria.

Abdominal angiostrongyliasis: a case with severe evolution

É relatado um caso de abdome agudo causado por angiostrongilíase abdominal. Um paciente de 42 anos, previamente hígido, apresentou queixa de nove dias de dor abdominal, constipação, disúria, febre e uma massa palpável na fossa ilíaca direita. Uma laparotomia exploradora foi realizada. Após o tratamento cirúrgico o paciente apresentou graves complicações.

Longitudinal clinical and serological survey of abdominal angiostrongyliasis in Guaporé, southern Brazil, from 1995 to 1999

Angiostrongilíase abdominal é uma zoonose causada pelo Angiostrongylus costaricensis, nematódeo que se localiza no interior de vasos mesentéricos. Nosso objetivo foi de abordar vários aspectos da história natural da parasitose, num estudo longitudinal clínico-sorológico. Um total de 179 indivíduos residentes em área rural no sul do Brasil, com transmissão ativa, foram seguidos por cinco anos. Neste período foram registradas prevalências de 28,2%, 4,2%, 10%, 20,2% e 2,8% e incidências de 0%, 5,9%, 8% e 1,5%. Tanto o sexo masculino quanto o feminino foram afetados com maiores frequências na faixa etária dos 30 aos 49 anos. Em 32 indivíduos, amostras de soro foram coletadas em todas as etapas e a reatividade de IgG detectada por ELISA foi variável e geralmente não persistindo mais do que um ano. Alguns padrões individuais foram sugestivos de re-infecção. Não houve associação com a ocorrência nem de dor abdominal nem com outras enteroparasitoses e não houve nenhum caso com diagnóstico confirmado (histopatológico) da infecção. Moluscos foram encontrados portando larvas infectantes de terceiro estadio, em algumas moradias, com uma prevalência geral de 16% e baixas cargas parasitárias. Em conclusão, a angiostrongilíase abdominal no sul do Brasil pode ser uma infecção frequente, porém com baixa morbidade e reatividade sorológica de gradual declínio.

Immunoblot evaluation of the specificity of the 29-kDa antigen from young adult female worms Angiostrongylus cantonensis for immunodiagnosis of human angiostrongyliasis.

The antigenic components of Angiostrongylus cantonensis young adult female worm somatic extract (FSE) were revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. The sera tested were from patients with proven angiostrongyliasis, other parasitic diseases, and healthy adults. Both the sera and cerebrospinal fluid (CSF) were tested from patients with clinical angiostrongyliasis. The CSF from patients with other neurological diseases were also included. Using SDS-PAGE, we found that the FSE comprised more than 30 polypeptides. Immunoblot analysis revealed at least 12 or 13 antigenic bands in patients with proven or clinical angiostrongyliasis, respectively. The patterns of reactivity recognized by the serum and CSF antibodies against FSE were similar. These antigenic components had molecular masses ranging from less than 14.4 to more than 94 kDa. The prominent antigenic band of 29-kDa might serve as a reliable marker for the diagnosis of angiostrongyliasis. The sensitivity, specificity, positive and negative predictive values of immunoblot analysis in this antigenic band were 55.6%, 99.4%, 83.3% and 97.4%, respectively.

Detection of the acute phase of abdominal angiostrongyliasis with a parasite-specific IgG enzyme linked immunosorbent assay

Angiostrongylus costaricensis may cause intestinal lesions of varied severity when it accidentally infects man in Central and South America. First-stage larvae have never been detected in stools. Therefore, a parasite-specific IgG ELISA was evaluated for the determination of the acute phase of infection. The specificity and the sensitivity of the immunoassay was shown to be 76.2 percent and 91.1 percent, respectively. Eight serum samples taken from patients with histopathological diagnosis, at different time points (3 to 15 months) after surgical treatment, showed a sharp and early decline in antibody reactivity. The titration of anti-A. costaricensis antibodies has proved to be a useful method for the diagnosis of acute abdominal angiostrongyliasis