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.

Angiostrongylus dujardini infection in a coconut lorikeet (Trichoglossus haematodus) from a zoological garden in Switzerland.

Angiostrongylus spp. (Metastrongyloidea) can cause severe disease in several animal species and humans. This report describes an infection with Angiostrongylus dujardini in a captive coconut lorikeet (Trichoglossus haematodus) from a zoo in Switzerland. The bird was reported being attacked by conspecifics, removed from the flock, and hospitalized. It showed lethargy, moderately reduced body condition, and lack of reaction to visual stimuli. Analgesic and antibiotic treatment were initiated but because of worsening of its general condition, the bird was euthanized the following day. Necropsy revealed multifocal, subcutaneous hemorrhages, diffusely reddened lungs and a moderately dilated right heart with several intraluminal nematodes embedded in a coagulum. Four worms were collected and microscopically examined. They were identified as adult females, measuring 19-21 mm long x 0.4-0.5 mm wide, with general morphological and morphometric characteristics consistent with angiostrongylid nematodes. In lung sections, multifocal collection of thin-walled embryonated eggs in variable stages of development was observed along with fully developed nematode larvae within the lumina of alveoli and lung vessels. Associated granulomatous infiltrates indicated a severe, multifocal, chronic, granulomatous pneumonia. The diagnosis of A. dujardini infection was formulated by morphological examination of adult and larval stages, supported by molecular analysis (PCR-amplification and sequencing of the ITS2, 5.8S and 28S rDNA flanking regions). This is the first report of A. dujardini infection in an avian species, providing evidence that birds can serve as accidental hosts of this parasite in addition to mammals, and that the parasite can reach maturity and multiply in the avian cardiorespiratory system.

A practical guide for the diagnosis of abdominal angiostrongyliasis caused by the nematode Angiostrongylus costaricensis.

Abdominal angiostrongyliasis (AA) is a severe parasitic infection caused by the nematode Angiostrongylus costaricensis. This disease is characterized by abdominal pain, a strong inflammatory eosinophilic response in the blood and tissues, and eventually intestinal perforation. Diagnosis of AA is challenging since there are no commercially available serological kits for A. costaricensis, and thus, histopathological analysis remains the gold standard. Herein we provide a decision flowchart for clinicians to improve the diagnosis of AA based on a patient's clinical manifestations, laboratory findings, macroscopic observations of the gut lesions, as well as characteristic microscopic alterations in biopsies. A brief discussion of the available polymerase chain reaction and in-house serological methods is also presented. The aim of this mini-review is to improve the diagnosis of AA, which should lead to prompt detection of cases and better estimates of the epidemiology and geographical distribution of A. costaricensis.

Abdominal angiostrongyliasis, report of two cases and analysis of published reports from Colombia. / Abdominal angiostrongyliasis, report of two cases and analysis of published reports from 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.

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.

Angiostrongyliasis infection masquerading as granulomatosis with polyangiitis: a case-based review.

Pulmonary angiitis is a small vessel vasculitis commonly reported in granulomatosis with polyangiitis (GPA) but is rarely attributed to angiostrongyliasis. We report a case of a patient with well-controlled rheumatoid arthritis, who was treated for GPA based on lung biopsy results with glucocorticoids (GC). Upon re-review of the initial pathology, along with peripheral eosinophilia and history of recent travel, the patient was eventually diagnosed with angiostrongylus-like nematode infection. GCs were subsequently discontinued and instead, the patient was treated with anthelmintics with complete resolution of symptoms. Commonly associated with eosinophilic meningitis or abdominal angiostrongyliasis in humans, clinical pulmonary manifestations of this parasite species are rare. With parasitic infiltration of the pulmonary vessels mimicking clinical GPA, diagnosis and treatment can be difficult in these patients. We discuss the third-reported case and first-reported survivor of Angiostrongylus-induced pulmonary angiitis followed by a focused review of the literature.

First report of Aelurostrongylus abstrusus in St. Kitts.

A 4-month-old intact male domestic shorthair kitten living in St Kitts, West Indies presented with respiratory distress, cachexia, and mucopurulent nasal discharge. Thoracic radiographs revealed a diaphragmatic hernia. The diaphragmatic hernia as well as subpleural pulmonary nodules suspicious for verminous pneumonia were identified during a postmortem examination. Histology showed multifocal to coalescing pyogranulomatous and eosinophilic pneumonia centered on larvae and morulated eggs. The lesion and nematode morphology were consistent with Aelurostrongylus abstrusus. Although Aelurostrongylus abstrusus has been reported worldwide, this is the first report of a metastrongyloid lungworm in cats in St. Kitts and for the West Indies. This case report should increase the awareness of A. abstrusus pneumonia in cats from St. Kitts and other locations in the eastern Caribbean.

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.

Application of Recombinant Angiostrongylus cantonensis Galectin-2 Protein for Serodiagnosis of Human Angiostrongyliasis by Immunoblotting.

Angiostrongyliasis is a foodborne disease caused by a zoonotic nematode, Angiostrongylus cantonensis, which produces eosinophilic meningitis or meningoencephalitis (EOM) in humans. Definitive diagnosis is rarely possible because worms are almost never recovered from patients. Human disease can be diagnosed by clinical symptoms and serological tests. Presently, diagnosis is performed by serological detection of antibodies against specific somatic antigens (molecular mass 29-31 kDa) extracted from female worms. The life cycle of A. cantonensis must be maintained in the laboratory to provide a source of this diagnostic antigen. Here, we cloned and expressed recombinant A. cantonensis galectin-2 (rAcGal2) corresponding to a 31-kDa antigenic peptide. Recombinant protein was purified and used in immunoblot tests, which showed reactions with human serum panels consisting of six confirmed angiostrongyliasis and 24 clinically diagnosed cases of EOM-associated with angiostrongyliasis, 160 samples from patients with other parasitic infections, and 30 samples from normal healthy subjects. Accuracy, sensitivity, specificity, and positive and negative predictive values were 95.0%, 93.3%, 95.3%, 75.7%, and 98.9%, respectively. The test was nonreactive with sera of human gnathostomiasis and cysticercosis, two diseases that could present similar neurological symptoms. Recombinant AcGal2 has potential as a diagnostic antigen and could replace native parasite antigens in further development of an angiostrongyliasis serodiagnostic test kit.

Severe Verminous Pneumonia Caused by Natural Mixed Infection with Aelurostrongylus abstrusus and Angiostrongylus chabaudi in a European Wildcat from Western Balkan Area.

AIMS: Aelurostrongylus abstrusus (Railliet, 1898) and Angiostrongylus chabaudi (Biocca, 1957) are important cardiopulmonary metastrongyloids in felids. This case report describes, for the first time, a natural and patent mixed infection caused by A. abstrusus and A. chabaudi in a European wildcat (Felis silvestris silvestris) from Bosnia and Herzegovina. Most important, this is a rare report of fatal parasitism in wildlife, involving a severe verminous bronchopneumonia and gastrointestinal nematode and cestode infection with Toxocara cati, Taenia taeniaeformis, Aonchotheca putorii, and Ancylostoma spp. RESULTS: Emphasis is set to detailed description of granulomatous, interstitial verminous bronchopneumonia, morphological description of A. abstrusus and A. chabaudi, and molecular confirmation of diagnosis by triplex PCR. CONCLUSION: The data provided in this study contribute to the knowledge on the epizootiology and pathological effect of these neglected metastrongyloids in European wildcat.

Larval survival of Aelurostrongylus abstrusus lungworm in cat litters.

OBJECTIVES: The dehydrating power of cat litters may reduce the vitality of first-stage larvae (L1s) of feline lungworms, limiting copromicroscopical diagnosis. This study assessed the effect of the most commonly used cat litters on Aelurostrongylus abstrusus L1 survival. METHODS: Four types of cat litters were used: clumpling clay (group A); non-clumpling clay (group B); silica crystals (group C); and biodegradable (group D). A control group without litter (group E) was also included. On study day 0 (T0), L1s were obtained by the Baermann-Wetzel technique from the faeces of a naturally infected cat and ~100 larvae were injected in each of the 20 lungworm larvae-free faecal samples (~2 g each). Thereafter, four faecal samples per group were transferred into plastic cups containing the four different types of cat litters, or into empty cups (group E). The survival of L1s was assessed in each group after 3 (T3), 6 (T6), 12 (T12) and 24 (T24) h, using the Baermann-Wetzel technique. RESULTS: A decreasing trend of L1 survival was observed in all groups, with highest significant values at T0 compared with T3, T6, T12 and T24 (P <0.001). However, at T24, a significantly higher number (P <0.05) of L1s was extracted from faeces of the control group compared with the four groups with cat litters. CONCLUSIONS AND RELEVANCE: This study demonstrates how the survival of A abstrusus L1s, and therefore diagnosis, may be negatively influenced by the litter. The effect is time dependent, with a reduction in the number of vital larvae according to the type of litter, over time. False-negative results may be obtained, especially in cases of low parasitic load or when the sample is collected many hours after the emission.

Immunochromatographic test for rapid serological diagnosis of human angiostrongyliasis.

OBJECTIVES: The serological diagnosis of human infection with Angiostrongylus cantonensis remains problematic because there are no commercially available validated tests. Most laboratories use domestically prepared tests such as the enzyme-linked immunosorbent assay (ELISA) or immunoblotting. Since laboratory facilities are not always available in endemic areas, we developed and assessed a rapid lateral flow immunochromatographic assay (AcQuickDx Test) to detect anti-A. cantonensis antibodies in human serum. METHODS: The test device was assembled with purified 31-kDa glycoprotein as diagnostic antigen and with gold-labelled anti-human immunoglublin-G as the detector reagent. A total of 97 serum samples were tested - 19 samples from clinically diagnosed patients with detectable A. cantonensis-specific antibody in immunoblotting; 43 samples from patients with other parasitic diseases, i.e. gnathostomiasis (n=13), toxocariasis (n=2), trichinellosis (n=2), hookworm infection (n=4), filariasis (n=5), cysticercosis (n=9), paragonimiasis (n=2), opisthorchiasis (n=3), and malaria (n=3); and 35 samples from normal healthy subjects. RESULTS: The sensitivity, specificity, positive predictive value and negative predictive value of AcQuickDx Test to detect anti-A. cantonensis specific antibodies in serologically confirmed angiostrongyliasis cases, were 100%, 98.72%, 95% and 100%, respectively. Positive AcQuickDx was observed in 1 of 4 cases with hookworm infections. No positive AcQuickDx was observed in cases with other parasitic diseases, and the individual healthy subjects. CONCLUSIONS: AcQuickDx Test is rapid, highly sensitive and specific, and easy to perform without additional equipment or ancillary supplies. It yields results that are interpreted visually, and possesses a long shelf-life at room temperature. Thus, it can be applied as an additional test for clinical diagnostic support of angiostrongyliasis either in conventional laboratories or for remote areas where laboratory infrastructure is not available.

Abdominal Angiostrongyliasis: A Presentation of Eosinophilic Granulomatous Colitis.

We present a case of a 4-year-old girl with abdominal angiostrongyliasis who presented with persistent fevers, hepatosplenomegaly, acute abdominal pain, and eosinophilia. Computed tomography scan identified thickening of the ascending colon with a narrowed lumen. Endoscopic evaluation revealed ulcerations and erythema in the ascending colon. The microscopic findings in biopsies included active chronic inflammation with prominent eosinophils and granulomas. A subset of granulomas contained the eggs of Angiostrongylus costaricensis. The definitive method of diagnosing A costaricensis is histology; peripheral blood serology has low specificity and the stool from infected patients does not contain eggs or larvae. Pathologists from endemic regions (Central and South America) are familiar with the typical histologic changes; however, because of increasing global travel, all pathologists should become familiar with A costaricensis, which may mimic common gastrointestinal diseases such as Crohn's disease, appendicitis, and Meckel's diverticulum.

Occurrence and clinical significance of Aelurostrongylus abstrusus and other endoparasites in Danish cats.

Feline endoparasites are highly prevalent worldwide and may cause a variety of clinical signs in infected cats. Prevalence rates are dynamic and there is limited knowledge of the current prevalence in Denmark and the clinical manifestation and significance of especially the lungworm Aelurostrongylus abstrusus. This study investigated the total and local prevalence of Aelurostrongylus abstrusus and other endoparasites in Danish cats. The clinical significance of feline aelurostrongylosis was also examined through identification of frequency and severity of selected clinical signs. Faecal samples (n=327) and clinical data (n=312) were collected from August to October 2015, primarily from outdoor cats located at shelters distributed across Denmark. A modified Baermann method and a concentration McMaster technique was used to diagnose A. abstrusus first stage larvae and eggs/oocysts of other endoparasites. The total A. abstrusus prevalence was 8.3% [95% CI: 5.6-11.9] but local prevalence rates varied from 0% [95% CI: 0.0-8.8] to 31.4% [95% CI: 16.9-49.3]. A rural habitat appeared to increase the risk of A. abstrusus and this accounted for most of the local variation. Furthermore, the risk of infection was lower in kittens younger than 11 weeks compared to older cats (p=0.002). The cats were also infected with Toxocara cati (44.4% [95% CI: 38.3-50.7]), taeniid species (8.9% [95% CI: 5.7-13.0]), Capillaria aerophila (3.1% [95% CI: 1.3-6.0]), Aonchotheca putorii (3.9% [95% CI: 1.9-7.0]), Cystoisospora felis (3.1% [95% CI: 1.3-6.0]) and Cystoisospora rivolta (2.3% [95% CI: 0.9-5.0]), but there was no difference in local distribution. Co-infection was common, as 66.7% of A. abstrusus infected cats were also infected with one or more other parasites, the most common being T. cati. However, none of these parasites were significantly associated with A. abstrusus. The vast majority of the A. abstrusus infected cats displayed mild to moderate clinical signs. The main symptoms associated with the infection were increased sound on auscultation of the lungs (p=0.002), increased respiratory rate (p=0.02), coughing (p=0.007) and enlarged mandibular lymph nodes (p=0.002). None of these symptoms were associated with T. cati or C. aerophila which may also affect the lungs. This supports that the symptoms may be related to A. abstrusus and that aelurostrongylosis should be considered an important differential diagnosis in any feline respiratory patient.

Single and mixed feline lungworm infections: clinical, radiographic and therapeutic features of 26 cases (2013-2015).

Objectives The aim of this study was to retrospectively describe clinical, radiographic and therapeutic features of feline lungworm infection. Methods Medical records of cats with lungworm diagnosis, thoracic radiography and without concurrent diseases between 2013 and 2015 were reviewed. Collection of data included physical examination, haematology, serum biochemistry, therapy with a variety of anthelmintics and outcomes. Results Thirty-seven records were recovered and 26 were included in the study. Single infections by Aelurostrongylus abstrusus (n = 15), Troglostrongylus brevior (n = 3) and Capillaria aerophila (n = 1) and coinfections by T brevior/ A abstrusus (n = 6) and T brevior/ C aerophila (n = 1) were diagnosed. The most common respiratory signs were coughing (n = 12), increased vesicular sounds (n = 10), dyspnoea (n = 9), such as laboured breathing, orthopnoea or open-mouth breathing, and tachypnoea (n = 6). Two cats were subclinically infected. The most common laboratory abnormality was anaemia (n = 7). Radiographic patterns recorded were interstitial (n = 24), bronchial (n = 21), alveolar (n = 10) and vascular (n = 2). Twenty-five cats had a complete recovery within 2-6 weeks of therapy. One kitten died 7 days after the diagnosis. Conclusions and relevance Lungworms should always be included in the differential diagnosis in cats living in endemic areas and presenting with respiratory signs and radiographic abnormalities. A copromicroscopic examination should be considered as the first diagnostic step for all cats at risk of lungworm infections. In most cases, timely therapy with a variety of anthelmintics guarantees recovery.