Angiostrongylus Costaricensis Research Articles

Diagnostic criteria and case definitions for abdominal angiostrongyliasis: a systematic review from the Brazilian experience.

Although rare, Angiostrongylus costaricensis infection may be a more prevalent etiology of inflammatory bowel disease than ulcerative colitis and Chron's disease in endemic areas in Central and South America. The present study reviewed the occurrence of A. costaricensis in Brazil, its clinical presentation and pathology; and proposed diagnostic criteria and case definitions for abdominal angiostrongyliasis (AA). Southern and southeastern Brazilian regions are the main endemic areas, and AA affects both genders and all age groups. A review of all 23 published reports of 51 Brazilian patients highlighted the following features that were subsequently classified as minor diagnostic criteria: abdominal pain, palpable mass in the right lower abdominal quadrant, history of exposure, ileocecal tumor, and intestinal perforation with wall thickening. Proposed major criteria include right lower quadrant abdominal pain, blood eosinophilia, positive serology (antibody detection), intense eosinophilic infiltration that involves all strata of the intestinal wall, eosinophilic granulomatous reaction, and eosinophilic vasculitis. In addition to the definitions of suspected and possible cases according to increasing strength of evidence of this infection, demonstration of worms/eggs/larvae in tissues or Angiostrongylus DNA in tissues or serum are required for a confirmed diagnosis. The application of the proposed criteria and definitions may improve patient management, epidemiologic surveillance, and identification of new endemic areas.

Relationship between histopathological lesions and oxidative stress in mice infected with Angiostrongylus costaricensis.

This study describes changes in oxidative stress (OS) parameters in mice experimentally infected with Angiostrongylus costaricensis, which causes abdominal angiostrongyliasis. For this, 28 Swiss mice were used, divided into two groups (G1 and G2), with 14 animals each. Of these, eight were infected with ten infective larvae each, by gavage, and six were used as a control group. Mice from G1 and G2 were euthanized at 14 days and 24 days post-infection, respectively. Tissue samples were used for histopathological analysis and blood (serum) samples were taken to assess the levels of proteins, non-protein thiols (NPTs) and nitric oxide (NO), from centrifugation and subsequent collection of aliquots of the supernatant. Among OS parameters, infected mice in both groups had higher NO levels than the control group, due to the presence of: eosinophil infiltrate in the liver and intestine; pancreatitis; and intestinal granuloma. However, the infected mice of both groups showed a reduction in the levels of NPTs, in relation to the control group, due to the presence of: eosinophilic infiltrate in the liver and intestine; and intestinal granuloma. Our results suggest that A. costaricensis infection has important effects on the intestine, liver and pancreas, and the analyses were performed from the tissue of these organs. The mechanisms for these changes are related to the decrease in the body's main antioxidant defences, as demonstrated by the reduction of NPTs, thus contributing to the development of more severe tissue damage. Thus, the objective of the present study was to evaluate the relationship between histopathological lesions and markers for OS.

Molecular diagnosis of abdominal angiostrongyliasis by PCR using serum samples.

Abdominal angiostrongyliasis (AA) is a zoonotic disease caused by the nematode Angiostrongylus costaricensis, which is endemic in southern Brazil. Humans become infected by ingesting third-stage (L3) larvae and are considered accidental hosts since neither eggs nor first-stage (L1) larvae are found in feces. The definitive diagnosis can be made by histopathologic examination of surgical specimens or intestinal biopsies. The present study assessed the use of PCR to carry out the molecular detection of AA from serum samples. A total of 62 human serum samples were divided into three groups: (i) 28 serum samples from human patients with presumptive histopathological diagnosis of AA; (ii) 23 serum samples from individuals with unknown serology for AA; (iii) 11 serum samples from patients that suffered from different parasitosis were included. The serum samples were initially tested by in-house indirect ELISA and then by PCR. A total of 14 samples were positive by ELISA, and 6 were positive by PCR. Six samples that were negative by ELISA were positive by PCR. Amplicons were sequenced, and Angiostrongylus DNA was confirmed. We conclude that PCR amplification can be used to confirm Angiostrongylus DNA in serum, which is especially important in cases where antibody levels are too low to be detected. It may also serve as a useful target for survey studies.

First report of a possible abdominal Angiostrongylus costaricensis in a French expatriate in the French Amazon.

Abdominal angiostrongyliasis is a parasitic disease caused by Angiostrongylus costaricensis. Cases have been reported from Texas to southern Argentina but not in the eastern part of the Amazon. We present the case of a 34-year-old French man living in French Guiana who had travelled to the Caribbean.

Identification of Novel Genes and Proteoforms in Angiostrongylus costaricensis through a Proteogenomic Approach.

RNA sequencing (RNA-Seq) and mass-spectrometry-based proteomics data are often integrated in proteogenomic studies to assist in the prediction of eukaryote genome features, such as genes, splicing, single-nucleotide (SNVs), and single-amino-acid variants (SAAVs). Most genomes of parasite nematodes are draft versions that lack transcript- and protein-level information and whose gene annotations rely only on computational predictions. Angiostrongylus costaricensis is a roundworm species that causes an intestinal inflammatory disease, known as abdominal angiostrongyliasis (AA). Currently, there is no drug available that acts directly on this parasite, mostly due to the sparse understanding of its molecular characteristics. The available genome of A. costaricensis, specific to the Costa Rica strain, is a draft version that is not supported by transcript- or protein-level evidence. This study used RNA-Seq and MS/MS data to perform an in-depth annotation of the A. costaricensis genome. Our prediction improved the reference annotation with (a) novel coding and non-coding genes; (b) pieces of evidence of alternative splicing generating new proteoforms; and (c) a list of SNVs between the Brazilian (Crissiumal) and the Costa Rica strain. To the best of our knowledge, this is the first time that a multi-omics approach has been used to improve the genome annotation of A. costaricensis. We hope this improved genome annotation can assist in the future development of drugs, kits, and vaccines to treat, diagnose, and prevent AA caused by either the Brazil strain (Crissiumal) or the Costa Rica strain.

Angiostrongylus costaricensis

Angiostrongylus costaricensis is a parasitic nematode and the causative agent of abdominal angiostrongyliasis (AA) in humans. This nematode was described in Costa Rica 50 years ago and since then it has been reported from the southern USA to northern Argentina and the Caribbean. The parasites have rodent definitive hosts that shed L1 larvae in their feces, and terrestrial mollusks as intermediate hosts that bear L3 in the fibromuscular tissues of the foot. Humans are accidental hosts, where presence of the parasite in mesenteric arteries leads to vasculitis and an intense granulomatous inflammatory eosinophilic reaction surrounding eggs or larvae located in the intestinal mucosa, preventing the release of L1 in feces.

Terrestrial Slugs in Neotropical Agroecosystems

Slugs can be important agricultural pests in tropical regions. They are also intermediate hosts of parasitic nematodes, such asAngiostrongylus costaricensisandA. cantonensis, which can cause abdominal and cerebral angiostrongyliasis in humans. Management of slugs in conventional agriculture has relied heavily in the use of pellets containing metaldehyde. In this article, we review cases of slug problems and their management in neotropical agroecosystems.

Terrestrial slugs in neotropical agroecosystems.

Slugs can be important agricultural pests in tropical regions. They are also intermediate hosts of parasitic nematodes, such as Angiostrongylus costaricensis and A. cantonensis, which can cause abdominal and cerebral angiostrongyliasis in humans. Management of slugs in conventional agriculture has relied heavily in the use of pellets containing metaldehyde. In this article, we review cases of slug problems and their management in neotropical agroecosystems.

Morphological and molecular evidence of Oslerus osleri (Nematoda: Filaroididae) in the Andean fox (Lycalopex culpaeus).

Oslerus osleri is a cosmopolitan filaroid nematode that parasitizes the respiratory system of domestic and wild canids. Natural infection by O. osleri is reported in the Andean fox (Lycalopex culpaeus) in this study. Nematodes, enclosed in small and compact fibrous nodules of 1 to 5mm in diameter, were found on the surface of the trachea near the bronchial bifurcation on four Andean foxes during necropsy (one from Cuzco, Peru and three from Northwestern Patagonia in Argentina). The nematodes were identified as O. osleri by morphological and molecular methods. Ribosomal and mitochondrial DNA analyses were performed amplifying the second internal transcribed spacer region (ITS-2), the partial cytochrome c oxidase 1 (cox1), and the large subunit of nuclear ribosomal RNA (LSU rRNA) genes. Sequences of the ITS-2 and LSU rRNA had a genetic variation of 1.5% and 1.0%, respectively, with previous sequences of O. osleri registered in Genbank. This is the first amplification of the cox1 gene of O. osleri and demonstrated an identity of 92% to Perostrongylus falciformis (KY365437), and 90% to Angiostrongylus cantonensis (KY779735) and Angiostrongylus costaricensis (AP017675).

Abdominal angiostrongyliasis: pathologic findings in Swiss mice infected with different doses of Angiostrongylus costaricensis.

Abdominal angiostrongyliasis is caused by Angiostrongylus costaricensis, the definitive and intermediate hosts of which are wild rodents and terrestrial molluscs, respectively. Humans are accidental hosts and can be infected by ingesting the third-stage (infective) larvae (L3). It remains unclear whether the number of L3 inoculated is related to lesion severity. Our aim was to analyse histopathological alterations in Swiss mice infected with different doses of A. costaricensis. Thirty-two mice were randomly divided into four groups (n = 8/group): uninfected, control mice; mice infected with a low dose (five L3); mice infected with an intermediate dose (15 L3); and mice infected with a high dose (30 L3). The frequency of intestinal thrombi, splenitis, eggs/larvae, hepatic infarction and acute pancreatitis differed among the groups, the last being considered a significant finding. We conclude that different infective doses alter the histopathological aspects of the infection in Swiss mice, those aspects being more pronounced at medium and high doses, with no effect on the development of the disease. This experimental model shows that the parasite life cycle can be maintained in Swiss mice through the inoculation of a low dose (five L3).

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.

The invasive giant African snail Lissachatina fulica as natural intermediate host of Aelurostrongylus abstrusus, Angiostrongylus vasorum, Troglostrongylus brevior, and Crenosoma vulpis in Colombia.

BackgroundSeveral metastrongyloid lungworms are unreported pathogens in Colombia. Angiostrongylus vasorum and Crenosoma vulpis target the cardiopulmonary system of domestic and wild canids. Aelurostrongylus abstrusus and Troglostrongylus brevior infect felids and considering that six wild felid species exist in Colombia, knowledge of feline lungworm infections is important for their conservation. The zoonotic metastrongyloids Angiostrongylus costaricensis and Angiostrongylus cantonensis can cause severe gastrointestinal and neurological diseases. Angiostrongylus costaricensis has been reported in Colombia, while Ang. cantonensis is present in neighbouring countries. Research on the epidemiology of metastrongyloids in Colombia and South America more broadly requires evaluating the role that gastropods play as intermediate hosts in their life cycles. This study assessed the prevalence of metastrongyloid larvae in populations of the invasive giant African snail, Lissachatina fulica, in Colombia.Methodology/Principal findingsA total of 609 Lissachantina fulica were collected from 6 Colombian municipalities. The snails were then cryo-euthanized, artificially digested and the sediments examined microscopically for the presence of metastrongyloid larvae. Based on morphological characteristics 53.3% (56/107) of the snails from Puerto Leguízamo (Department of Putumayo) were infected with Ael. abstrusus larvae, 8.4% (9/107) with Ang. vasorum larvae, 6.5% (7/107) with T. brevior larvae and 5.6% (6/107) with C. vulpis larvae, being the region with highest prevalences of the four species. Snails from Andes (Department of Antioquia) and Tulúa (Department of Valle del Cauca) were positive for Ang. vasorum larvae with a prevalence of 4.6 (11/238) and 6.3% (4/64), respectively. Species identifications were confirmed by PCR and sequencing.Conclusions/SignificanceThis epidemiological survey reports for first time the presence of Ael. abstrusus, T. brevior, C. vulpis and Ang. vasorum in L. fulica in a number of regions of Colombia.

Activity profiling of peptidases in Angiostrongylus costaricensis first-stage larvae and adult worms.

BackgroundAngiostrongylus costaricensis is a relatively uncharacterized nematode that causes abdominal angiostrongyliasis in Latin America, a human parasitic disease. Currently, no effective pharmacological treatment for angiostrongyliasis exists. Peptidases are known to be druggable targets for a variety of diseases and are essential for several biological processes in parasites. Therefore, this study aimed to systematically characterize the peptidase activity of A. costaricensis in different developmental stages of this parasitic nematode.Methodology/Principal findingsA library of diverse tetradecapeptides was incubated with cellular lysates from adult worms and from first-stage larvae (L1) and cleaved peptide products were identified by mass spectrometry. Lysates were also treated with class specific peptidase inhibitors to determine which enzyme class was responsible for the proteolytic activity. Peptidase activity from the four major mechanistic classes (aspartic, metallo, serine and cysteine) were detected in adult worm lysate, whereas aspartic, metallo and serine-peptidases were found in the larval lysates. In addition, the substrate specificity profile was found to vary at different pH values.Conclusions/SignificanceThe proteolytic activities in adult worm and L1 lysates were characterized using a highly diversified library of peptide substrates and the activity was validated using a selection of fluorescent substrates. Taken together, peptidase signatures for different developmental stages of this parasite has improved our understanding of the disease pathogenesis and may be useful as potential drug targets or vaccine candidates.

Shedding of Angiostrongylus costaricensis larvae in the faeces of Swiss mice experimentally infected with different infective doses.

Abdominal angiostrongyliasis is an endemic zoonosis in southern Brazil caused by the nematode Angiostrongylus costaricensis, which uses terrestrial molluscs as intermediate hosts and wild rodents as final hosts. Humans can be infected by ingesting infectious A. costaricensis larvae. To date, correlations between shedding of first-stage larvae (L1) and different infective doses of third-stage larvae (L3) have not been elucidated. The aim of this study was to assess L1 faecal shedding levels in Swiss mice experimentally infected with different doses of A. costaricensis L3 and to determine whether infective doses are related to mortality. Thirty-two male Swiss mice were divided evenly into a non-infected control (NI-Con); low-dose infection (LD-Inf); medium-dose infection (MD-Inf) and high-dose infection (HD-Inf) groups infected with 0, 5, 15 and 30 A. costaricensis L3, respectively. Faecal samples were collected from each animal, starting at day 20 post infection. HD-Inf mice had greater faecal L1 shedding levels than LD-Inf mice, but not a significantly shortened survival. In conclusion, infective doses of A. costaricensis L3 affect L1 shedding levels without altering mortality in Swiss mice.

Invasive slug Meghimatium pictum (Stoliczka, 1873) infected by Angiostrongylus costaricensis Morera & Céspedes, 1971, and the possible risk of human infection associated with grape consumption.

Many molluscs may be infected with angiostrongylid larvae. Following the histopathological diagnosis of abdominal angiostrongyliasis in a grape farmer from southern Brazil, molluscs in the area were investigated. During a nocturnal search, 245 specimens of slugs were collected and identified as the invasive Chinese slug Meghimatium pictum. Angiostrongylus costaricensis worms were recovered from mice that were experimentally infected with larvae obtained from 11 (4.5%) of the molluscs. This study presents the first report of M. pictum being identified as an intermediate host for A. costaricensis. Most of the slugs were collected from grape plants, which suggests that transmission may be associated with grape consumption.

Angiostrongylus costaricensis infection in Martinique, Lesser Antilles, from 2000 to 2017.

Human abdominal angiostrongyliasis (HAA) is a parasitic disease caused by the accidental ingestion of the nematode Angiostrongylus costaricensis in its larval form. Human infection can lead to severe ischemic and inflammatory intestinal lesions, sometimes complicated by life-threatening ileal perforations. Only one case had been reported in Martinique, an Island in the French Antilles, in 1988. We retrospectively reviewed the medical charts of patients diagnosed with abdominal angiostrongyliasis at the University Hospital of Martinique between 2000 and 2017. The objectives of this study were to evaluate the incidence and perform a descriptive analysis of the clinical, biological, radiological, and histopathological features of HAA in Martinique. Two confirmed cases and two probable cases were identified in patients aged from 1 to 21 years during the 18-year period, with an estimated incidence of 0.2 cases per year (0.003 case/year/100.000 inhabitants (IC95% = 0.00–0.05)). All patients presented with abdominal pain associated with high blood eosinophilia (median: 7.24 G/L [min 4.25; max 52.28 G/L]). Two developed ileal perforation and were managed by surgery, with diagnostic confirmation based on histopathological findings on surgical specimens. The other two cases were probable, with serum specimens reactive to Angiostrongylus sp. antigen in the absence of surgery. All cases improved without sequelae. The description of this case series highlights the need to increase awareness of this life-threatening disease in the medical community and to facilitate access to specific diagnostic tools in Martinique. Environmental and epidemiological studies are needed to broaden our knowledge of the burden of this disease.

High-dose enoxaparin in the treatment of abdominal angiostrongyliasis in Swiss mice

Abdominal angiostrongyliasis (AA) is caused by Angiostrongylus costaricensis, which inhabits mesenteric arteries. There is no drug treatment for AA, and since intestinal infarction due to thrombi is one of the main complications of the disease, the use of anticoagulants may be a treatment option. Thus, we aimed to assess the effect of high doses of enoxaparin on the prevention of ischaemic intestinal lesions and on the survival of mice infected with A. costaricensis. Twenty-four mice were infected with L3 of A. costaricensis and divided equally into two groups: Group 1, control treated with placebo, and Group 2, treated daily with enoxaparin (2.5 mg/kg) for 50 days. All mice were subjected to necropsy and histological analysis. The results from gross and microscopic assessments showed no variation in the prevalence of lesions between the groups. An analysis was also performed among survivors and non-survivors, showing that animals that died often presented lesions, such as granulation tissue in the serosa, and intestinal infarction and adhesion. The mortality rate did not vary between the enoxaparin-treated and control groups. Thus, we showed that high doses of enoxaparin have no protective effect against AA, as the survival rates and lesions of mice did not vary between the treated and control groups. Considering that the use of prophylactic doses was also shown to be ineffective in a previous study, we do not recommend the use of enoxaparin for AA treatment.

Natural infection of the feline lungworm Aelurostrongylus abstrusus in the invasive snail Achatina fulica from Argentina

The giant African snail Achatina fulica is an invasive mollusk native to Africa, the first record in Argentina was in Puerto Iguazú, in northeastern Argentina in 2010. Recently it was reported in Corrientes Province. This snail can act as an intermediate host of Metastrongyloidea nematodes of importance in public health as: Angiostrongylus cantonensis, Angiostrongylus costaricensis and Angiostrongylus vasorum. Taking into account the presence of A. fulica in Argentina, the objectives of this study is to assess the presence of Metastrongyloidea nematodes in this mollusk species in Puerto Iguazú, Misiones, close to the international border with Brazil and Paraguay. A total of 451 samples were collected from February 2014 to November 2015. The snails were processed using a digestion technique to recover the parasites. A total of 206 nematodes larvae were founded in the digestion solution of 10 hosts (P=2%; MA=0.5; MI=21). Third larval stage (L3) nematodes identified as Aelurostrongylus abstrusus were founded parasitizing the snails. No other larval stage was observed. This species has veterinary importance because it causes ‘aelurostrongilosis’, also known as feline strongyloidosis. This study constitutes the first record of a Metastrongyloidea nematode in A. fulica in Argentina and also highlights the susceptibility of this mollusk as intermediate host of other helminthes of health importance. The present study suggests that there is a need to establish an epidemiological monitoring system in order to prevent the possible installation of an infected mollusks focus.

The white-nosed coati (Nasua narica) is a naturally susceptible definitive host for the zoonotic nematode Angiostrongylus costaricensis in Costa Rica

Angiostrongylus costaricensis (Strongylida, Angiostrongylidae) is a roundworm of rodents, which may cause a severe or fatal zoonosis in several countries of the Americas. A single report indicated that the white-nosed coati (Nasua narica), acts as a potential free-ranging wildlife reservoir. Here we investigated the prevalence and features of A. costaricensis infection in two procyonid species, the white-nosed coati and the raccoon (Procyon lotor) from Costa Rica to better understand their possible role in the epidemiology of this zoonotic infection. Eighteen of 32 (56.2%) white-nosed coatis collected between July 2010 and March 2016 were infected with A. costaricensis but none of 97 raccoons from the same localities were diagnosed with this infection. First-stage larvae of A. costaricensis were obtained from feces of 17 fresh white-nosed coati carcasses by Baermann technique. Parasite identity was confirmed by morphology, histology and molecular characterization of target genes. These data demonstrate that the white-nosed coati is a naturally susceptible definitive host for A. costaricensis in Costa Rica contrary to findings in the raccoon.

Prevalencia de larvas de angiostrongylus costaricensis (nematoda: angiostrongylidae) en babosas vaginulus plebeius (mollusca:veronicellidae) de Costa Rica

Slugs (Vaginulus plebeius) random collections were conducted during the rainiest months of the year between September 2001 and October 2007 in order to evaluate the prevalence of the parasite Angiostrongylus costaricensis in these Mollusca in their natural environment, and the risk involved for the population. Samples were taken at 50 of the 81 cantons of the country, for a total sample of 8870, finding a 3.9% infected mollusca. 48% of the cantons showed positive mollusca, San Jose was the province with the highest percentage of infection (5.7 %) and the lowest at Carthage 1.3%. as to the cantons Alajuelita was the city with the highest prevalence (27.4%). Finding a decrease in infection levels reported in the decades of the eighties and nineties (44%-69%), possibly due to the sampling technique and population changes over the last 25 years.