Angiostrongylus Vasorum Infection Research Articles

First case of autochthonous Angiostrongylus vasorum infection in a Norwegian dog

A fifteen-month-old Pembroke Welsh corgi with respiratory distress, exercise intolerance, and moderate regenerative anemia was referred to The Norwegian University of Life Sciences, Small Animal Hospital.Hematology revealed moderate regenerative anemia without evidence of hemolysis. Thoracic radiographs showed a generalized mixed interstitial to alveolar lung pattern and enlarged pulmonary arteries. Changes suggestive of moderate pulmonary hypertension were noted on echocardiography. Baermann fecal diagnostic flotation identified large numbers of Angiostrongylus vasorum larvae, and the AngioDetect serological antigen test was positive. The dog was treated with a two-week course with fenbendazole (51 mg/kg q24h po) and topical imidacloprid/moxidectin (250 mg/62.5 mg) and a one-week course with sildenafil (0.45 mg/kg q12h po). Complete clinical, clinicopathological and echocardiographic resolution was observed after only four weeks. Rapid improvement of echocardiographic abnormalities in cases with suspected pulmonary hypertension is not usually reported in cases with angiostrongylosis.Infection with A. vasorum should be considered in dogs with respiratory signs and bleeding tendencies, even in countries with no endemic history or reported cases.

Epidemiology of Angiostrongylus vasorum and Crenosoma vulpis infection in dogs in Denmark.

This retrospective study aimed to evaluate the risk factors (age and breed group) associated with Angiostrongylus vasorum and Crenosoma vulpis infection in dogs. Faecal examinations obtained in dogs from January 2016 to December 2021 as part of routine clinical practice at two veterinary clinics in the Odsherred region of Zealand, Denmark, were included in this study. Faecal samples were analysed using the Baermann technique for nematode detection. Samples were collected from two clinics located in Northwestern Zealand, Denmark. Multinomial regression analysis, quasi-Poisson models and a generalised additive model for linearity were used to analyse the data. A total of 2,013 faecal samples were included in the study. Age was a significant risk factor for a positive Baermann, with a negative linear relationship observed (A. vasorum odds ratio: 0.80, 95% confidence interval: 0.70 to 0.91, C. vulpis odds ratio: 0.95, 95% confidence interval: 0.91 to 0.99, both nematodes: odds ratio: 0.87, 95% confidence interval: 0.77 to 0.99). Breed group analysis considering retrievers and flushing and water dog as reference group, demonstrated that sheep- and cattle dogs had a reduced risk of C. vulpis infection (odds ratio: 0.49, 95% confidence interval: 0.24 to 0.97), whereas dachshunds had an increased risk of A. vasorum infection (odds ratio: 3.28, 95% confidence interval: 1.14 to 9.47). Variations in the number of nematodes was found, with companion and toy dogs exhibiting higher numbers of C. vulpis (incidence rate ratio: 21.40, 95% confidence interval: 2.88 to 159) and sheep- and cattle dogs displaying higher numbers of A. vasorum (incidence rate ratio: 30.20, 95% confidence interval: 7.33 to 125). The prevalence rates of C. vulpis and A. vasorum were estimated at 14.50% (95% confidence interval: 13 to 16.10) and 3.40% (95% confidence interval: 2.70 to 4.30), respectively. There are significantrisk factors for nematode infection in dogs that can be considered for proper preventive care of this condition.

Is the Angiostrongylus vasorum infection in domestic dogs underestimated or misdiagnosed? A comprehensive presentation of four lethal cases.

Angiostrongylus vasorum (A. vasorum) is a widely distributed gastropod-borne nematode, causing severe cardio-pulmonary disorders in dogs. In Romania, A. vasorum was detected in foxes and serologically confirmed in domestic dogs, but no clinical cases are currently diagnosed. Four dogs with clinical history of respiratory distress, originating from different geographical regions of Romania, were included in the study. One dog (case 1) was clinically evaluated using thoracic radiology and cardiac ultrasound; examination of feces and PCR were also performed for the etiologic diagnosis. The postmortem exam was performed in the other three cases, followed by parasitological and molecular analyses. In the first case, parasitic pneumonia was suspected based on the radiographic examination of the thorax and the infection with A. vasorum was confirmed by L1 morphological identification and PCR. The main postmortem changes included large, coalescing, dark red areas of pulmonary consolidation (n = 3) and numerous adult nematodes in the pulmonary arteries (n = 2). The histopathological examination of the lungs showed necrotizing and granulomatous pneumonia with severe hemorrhages and chronic pulmonary arterial changes. Intralesional nematodes were seen in all necropsied cases. Additional inflammatory changes related to A. vasorum infection were identified in the brain and tracheobronchial and mediastinal lymph nodes (n = 2). Identification of larvae, histopathology and PCR confirmed the infection with A. vasorum. This study describes the first cases of canine cardiopulmonary angiostrongylosis in domestic dogs in Romania, and focuses on clinical presentation, pathological findings and molecular analysis. Angiostrongylosis should be included on the list of differential diagnoses of canine cardiopulmonary distress and/or haemorrhagic diathesis in Romania and awareness should be raised among clinicians to avoid post-mortem diagnosis in the future.

Can IDEXX Angio Detect™ accurately detect canine Angiostrongylosis?

PICO question
 In dogs, is IDEXX Angio Detect™ as accurate as Baermann coprology when diagnosing Angiostrongylus vasorum infection?
 
 Clinical bottom line
 Category of research question
 Diagnosis
 The number and type of study designs reviewed
 Eight papers were critically reviewed: three diagnostic accuracy studies, two cross-sectional studies (one of which also included a retrospective case series), one cohort study, one case-control study, and one case series
 Strength of evidence
 Weak
 Outcomes reported
 Angio Detect™ (IDEXX) was shown to have low-moderate sensitivity and high specificity in comparison to Baermann coprology. Occasionally, false-negative results occurred with Angio Detect™ when compared to Baermann coprology. This was thought to be due to antigen-antibody complex formation. Positive Angio Detect™ assays were obtained in both symptomatic and asymptomatic canine patients. In an experimental setting, Angio Detect™ was shown to obtain a positive result five weeks post-inoculation
 Conclusion
 There is weak evidence supporting Angio Detect™ as a highly specific and moderately sensitive diagnostic test when compared to Baermann coprology
 
 How to apply this evidence in practice
 The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.
 Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.
 

Fox Serum Proteomics Analysis Suggests Host-Specific Responses to Angiostrongylusvasorum Infection in Canids.

Dogs infected with the cardiopulmonary nematode Angiostrongylus vasorum may suffer from respiratory distress and/or bleeding disorders. Descriptions of clinical signs in foxes are rare, despite high prevalence. To evaluate the impact of infection on coagulation and immune response, serum proteins from eight experimentally infected foxes before and after inoculation (day 0, 35, 84, 154) were subjected to differential proteomic analyses based on quantitative data and compared to available data from dogs. The number of proteins with differential abundance compared to the uninfected baseline increased with chronicity of infection. Bone marrow proteoglycan, chitinase 3-like protein 1 and pulmonary surfactant-associated protein B were among the most prominently increased proteins. The abundance of several proteins involved in coagulation was decreased. Enriched pathways obtained from both increased and decreased proteins included, among others, “platelet degranulation” and “haemostasis”, and indicated both activation and suppression of coagulation. Qualitative comparison to dog data suggests some parallel serum proteomic alterations. The comparison, however, also indicates that foxes have a more adequate immunopathological response to A. vasorum infection compared to dogs, facilitating persistent infections in foxes. Our findings imply that foxes may be more tolerant to A. vasorum infection, as compared to dogs, reflecting a longer evolutionary host–parasite adaptation in foxes, which constitute a key wildlife reservoir.

Coagulation Status in Dogs Naturally Infected with Angiostrongylus vasorum.

Angiostrongylus vasorum infection has been associated with coagulopathies including hyperfibrinolysis. We compared coagulation status including thromboelastometry (ROTEM) parameters in dogs naturally infected with A. vasorum versus healthy dogs to determine clinicopathological parameters associated with bleeding, hypocoagulopathy, and hyperfibrinolysis. Clinical signs, white blood cell count, platelet count, hematocrit, plasmatic coagulation tests (PT, aPTT, fibrinogen concentration), D-dimer, and ROTEM S parameters (Ex-tem, In-tem, Fib-tem, Ap-tem) were analysed and compared between bleeding, nonbleeding, and control dogs and between hypo- and normocoagulable animals. Clinical signs of bleeding were present in 6/9 (67%) hypocoagulable and 1/9 (11%) normocoagulable dogs. PT, fibrinogen concentration, and several ROTEM parameters were significantly different between hypocoagulable and normocoagulabe A. vasorum infected dogs. Hyperfibrinolysis was identified in 44% of infected dogs and was significantly more common in bleeding and hypocoagulable dogs. Hyperfibrinolysis was significantly associated with low MCFFib-tem but not with low fibrinogen concentration or increased D-dimers. CFTEx-tem > 248 swas 100% sensitive and 89% specific to predict hyperfibrinolysis. Hyperfibrinolysis, hypocoagulability and bleeding are common in A. vasorum infected dogs. Only Ex-tem and Fib-tem parameters and potentially PT were associated with bleeding or hypocoagulability. Ex-tem analysis enables detection of bleeding, hypocoagulability and hyperfibrinolysis within minutes.

Spontaneous tricuspid valve chordal rupture in a dog with severe, irreversible pulmonary hypertension caused by Angiostrongylus vasorum infection

BackgroundThe adult worms of Angiostrongylus vasorum reside in the pulmonary artery of dogs and can lead to cardiac, respiratory, and central neurologic signs. Due to luminal obstruction and perivascular inflammation of the pulmonary artery branches, pulmonary hypertension can arise. Pulmonary hypertension, in turn, can lead to severe damage of the right-sided cardiac structures, leading to right ventricular remodeling and tricuspid valve regurgitation.Case presentationAn 8-year-old neutered female English Cocker Spaniel was presented to the author’s institution because of abdominal distention and exercise intolerance. Ascites caused by congestive right-sided heart failure was found to be responsible for these problems. The underlying etiology of the right-sided heart failure was a severe pulmonary hypertension caused by Angiostrongylus vasorum infection. Echocardiography revealed, in addition to a severe concentric and eccentric right ventricular hypertrophy, right atrial and pulmonary trunk dilation, severe tricuspid valve regurgitation, and a systolic flail of the anterior leaflet of the tricuspid valve, resulting from ruptured chordae tendineae. As a coincidental finding, a congenital mitral stenosis was found. Oral therapy was initiated with daily administration of fenbendazole for 2 weeks along with daily administration of oral sildenafil until the re-check examination. At the 6-week re-check the dog showed full clinical and partial echocardiographic recovery, and both the blood antigen test for Angiostrongylus vasorum and the fecal Baermann larva isolation test were negative. When the sildenafil therapy was ceased after tapering the daily dosage, the owner reported recurrence of abdominal distension. Re-starting the sildenafil therapy resulted in resolution of this problem. The dog was reported to be clinically healthy with daily sildenafil administration 7 months after the initial presentation.ConclusionsThe present case report describes a dog where angiostrongylosis led to congestive right-sided heart failure resulting from severe pulmonary hypertension. The secondary right ventricular eccentric hypertrophy together with suspected papillary muscular ischemia were the suspected cause of the ruptured major tricuspid chordae tendineae, which led to a severe tricuspid valve regurgitation. Despite eradication of the worms, the severe pulmonary hypertension persisted. Treatment with daily oral sildenafil, a pulmonary arterial vasodilator, was enough to keep the dog free of clinically apparent ascites.

Efficacy of orally administered combination of moxidectin, sarolaner and pyrantel (Simparica Trio\u2122) for the prevention of experimental Angiostrongylus vasorum infection in dogs

BackgroundInfection with Angiostrongylus vasorum may cause severe clinical disease, even death in dogs, however, due to the often non-specific clinical signs, diagnosis is not always straightforward. Regular prophylactic treatment may offer a safe means to protect dogs against infection. The efficacy of a novel oral endectocide containing moxidectin, sarolaner and pyrantel was investigated for the prevention of angiostrongylosis in dogs in three placebo-controlled, randomized, masked studies. The initial study (Study 1) determined the efficacious dosage of moxidectin in the combination product by evaluating three different dose levels, and two follow-up studies (Studies 2 and 3) confirmed the efficacy of the selected moxidectin dose.MethodsAnimals were infected orally with 200 infective third-stage larvae (L3) of A. vasorum and were treated 28 days later with the combination product or with placebo. Timing of dosing relative to infection allowed for efficacy to be evaluated against the immature adult (L5) stage. Dogs in Study 1 received treatments with oral tablets to deliver 3, 12 or 24 µg/kg moxidectin in combination with 2 mg/kg sarolaner and 5.0 mg/kg pyrantel (as pamoate salt) or placebo. In Studies 2 and 3, Simparica Trio™ tablets were administered to provide minimum dosages of 1.2 mg/kg sarolaner, 24 µg/kg moxidectin and 5.0 mg/kg pyrantel (as pamoate salt). Efficacy of the combination product was calculated as the percent reduction in adult worm counts at necropsy relative to placebo.ResultsIn Study 1, the 3, 12 and 24 µg/kg moxidectin dosage in the combination product provided 7.2%, 54.5% and 94.7% efficacy against the immature adult stages of A. vasorum, respectively. Studies 2 and 3 confirmed that the efficacy of 24 µg/kg moxidectin combined with 1.2 mg/kg sarolaner and 5 mg/kg pyrantel in Simparica Trio™ was ≥ 92.9%. All three studies established that a single oral administration of 24 µg/kg moxidectin in the combination product provided effective prophylactic treatment for angiostrongylosis, reduced L1 production and fecal excretion and minimized the tissue damage to the lungs.ConclusionsA single oral treatment of dogs with Simparica Trio™ providing moxidectin at a minimum dose of 24 µg/kg was efficacious in the prevention of angiostrongylosis.

The 'French heartworm' in Greece: A countrywide serological survey of Angiostrongylus vasorum infection by combined detection of circulating antigens and specific antibodies.

Angiostrongylus vasorum is a nematode of the superfamily Metastongyloidea and was first described in the south of France in the nineteenth century where its biology was extensively studied in the 1960ies, leading to the common use of the byname "the French heartworm". The life cycle of the parasite is indirect including slugs and snails as intermediate hosts, while the adults live in the right heart and pulmonary arteries. Since then, many studies have been conducted in different European countries. However, there is scant knowledge regarding the prevalence and distribution of this parasite in Greece. Therefore, the objective of the present study was to investigate the current seroprevalence of A. vasorum in dogs in Greece. Overall 1000 apparently healthy and randomly selected dogs, presented in veterinary clinics, were involved at national level (n=66 locations). Individual serum samples were obtained and tested using two in-house ELISAs by combining the detection of specific antibodies against the parasite and of circulating antigens of A. vasorum. Overall, 3.0% (n=30, CI 95% 2.1 to 4.3%) of the sampled dogs were seropositive to at least one of the two ELISAs: 0.4% (n=4, CI 95% 0.2 to 1.0%) were positive by both ELISAs, while 1.0% (n=10, CI 95% 0.5 to 1.8%) were seropositive only for specific antibodies and 1.6% (n=16, CI 95% 1.0 to 2.6%) were antigen-positive only. This is the first multicentric seroepidemiological study about A. vasorum in dogs from Greece. We showed that this parasite circulates in the local canine population and further studies should be carried out to elucidate its significance in the country.

A review of hyperfibrinolysis in cats and dogs.

The fibrinolytic system is activated concurrently with coagulation; it regulates haemostasis and prevents thrombosis by restricting clot formation to the area of vascular injury and dismantling the clot as healing occurs. Dysregulation of the fibrinolytic system, which results in hyperfibrinolysis, may manifest as clinically important haemorrhage. Hyperfibrinolysis occurs in cats and dogs secondary to a variety of congenital and acquired disorders. Acquired disorders associated with hyperfibrinolysis, such as trauma, cavitary effusions, liver disease and Angiostrongylus vasorum infection, are commonly encountered in primary care practice. In addition, delayed haemorrhage reported in greyhounds following trauma and routine surgical procedures has been attributed to a hyperfibrinolytic disorder, although this has yet to be characterised. The diagnosis of hyperfibrinolysis is challenging and, until recently, has relied on techniques that are not readily available outside referral hospitals. With the recent development of point-of-care viscoelastic techniques, assessment of fibrinolysis is now possible in referral practice. This will provide the opportunity to target haemorrhage due to hyperfibrinolysis with antifibrinolytic drugs and thereby reduce associated morbidity and mortality. The fibrinolytic system and the conditions associated with increased fibrinolytic activity in cats and dogs are the focus of this review article. In addition, laboratory and point-of-care techniques for assessing hyperfibrinolysis and antifibrinolytic treatment for patients with haemorrhage are reviewed.

Angiostrongylus vasorum infection in dogs from a cardiopulmonary dirofilariosis endemic area of Northwestern Italy: a case study and a retrospective data analysis

BackgroundIn Italy, Angiostrongylus vasorum, an emergent parasite, is being diagnosed in dogs from areas considered free of infection so far. As clinical signs are multiple and common to other diseases, its diagnosis can be challenging. In particular, in areas where angiostrongylosis and dirofilariosis overlap, a misleading diagnosis of cardiopulmonary dirofilariosis might occur even on the basis of possible misleading outcomes from diagnostic kits.Case presentationTwo Cavalier King Charles spaniel dogs from an Italian breeding in the Northwest were referred to a private veterinary hospital with respiratory signs. A cardiopulmonary dirofilariosis was diagnosed and the dogs treated with ivermectin, but one of them died. At necropsy, pulmonary oedema, enlargement of tracheo-bronchial lymphnodes and of cardiac right side were detected. Within the right ventricle lumen, adults of A. vasorum were found. All dogs from the same kennel were subjected to faecal examination by FLOTAC and Baermann’s techniques to detect A. vasorum first stage larvae; blood analysis by Knott’s for Dirofilaria immitis microfilariae, and antigenic tests for both A. vasorum (Angio Detect™) and D.immitis (DiroCHEK® Heartworm, Witness®Dirofilaria). The surviving dog with respiratory signs resulted positive for A. vasorum both at serum antigens and larval detection. Its Witness® test was low positive similarly to other four dogs from the same kennel, but false positive results due to cross reactions with A. vasorum were also considered. No dogs were found infected by A. vasorum.Eventually, the investigation was deepened by browsing the pathological database of Veterinary Pathology Laboratories at Veterinary School of Milan University through 1998–2016, where 11 cases of angiostrongylosis were described. Two out of 11 dogs had a mixed infection with Crenosoma vulpis.ConclusionThe study demonstrates the need for accurate surveys to acquire proper epidemiological data on A. vasorum infection in Northwestern Italy and for appropriate diagnostic methods. Veterinary clinicians should be warned about the occurrence of this canine parasite and the connected risk of a misleading diagnosis, particularly in areas endemic for cardiopulmonary dirofilariosis.

Performance of the Angio Detect™ in-clinic test kit for detection of Angiostrongylus vasorum infection in dog samples from Europe

Angiostrongylosis is a crucial differential diagnosis in any dog with respiratory, bleeding, neurological, or syncopal signs of unknown etiology in endemic areas. Many cases of angiostrongylosis have a fatal outcome; subclinical angiostrongylosis also has been reported. The most common method for supporting diagnosis of angiostrongylosis has been identification of Angiostrongylus vasorum first stage larvae in the feces by the Baermann-Wetzel method. Although considered as gold standard, this method has technical and sampling challenges and cannot detect infections during prepatency or in case of intermittent shedding of the larvae. A rapid in-clinic antigen test has been developed for serologic detection of A. vasorum infections using blood samples (Angio Detect™, IDEXX Laboratories Inc., Westbrook, Maine, USA). The study reported here was conducted to determine diagnostic sensitivity and specificity of the Angio Detect test kit by comparing Angio Detect testing results using serum or plasma samples with the results of Baermann-Wetzel testing using matched fecal samples. Samples from 214 dogs [with clinically suspected (N=195) or diagnosed angiostrongylosis (N=19)] were used for this evaluation. Baermann-Wetzel testing was performed independently at commercial reference laboratories or at university hospitals. All serum/plasma samples were blinded and randomized before testing with Angio Detect. The Angio Detect test was positive for 34 of the 35 cases found positive by the Baermann-Wetzel method; sensitivity of the Angio Detect test was 97.1% (95%CI: 85.1%–99.9%). The Angio Detect test was negative for 177 of 179 samples that were negative by the Baermann-Wetzel test; specificity was 98.9% (95%CI: 96.0%–99.9%). In cross-reactivity testing, all 89 samples from dogs confirmed to be infected with other common nematodes (Dirofilaria immitis, D. repens, Crenosoma vulpis, hookworms, ascarids, or whipworms) were all negative for A. vasorum by the Angio Detect antigen test. Angio Detect provides a rapid and reliable method for diagnosis of A. vasorum in clinically suspected dogs at risk for infection. The test requires minimal steps by the operator and provides results in 15min, allowing the clinician to initiate treatment for positive dogs before leaving the clinic.

Monthly administrations of milbemycin oxime plus afoxolaner chewable tablets to prevent Angiostrongylus vasorum infection in dogs.

BackgroundInfection of dogs with the cardiopulmonary nematode Angiostrongylus vasorum may result in severe clinical disease therefore adequate prevention is necessary. A randomized, negative control, blinded study was conducted to evaluate the efficacy in the prevention of canine A. vasorum infection after monthly administrations of NexGard Spectra®, a novel chewable tablet formulation combining the insecticide and acaricide afoxolaner and the anthelmintic milbemycin oxime, in a multiple challenge (trickle infection) model.MethodsTwenty beagle dogs were challenged orally with doses of approximately 32–43 third-stage larvae of A. vasorum once every other week on seven occasions (Study Days -7, 7, 21, 35, 49, 63 and 77). Ten dogs were administered NexGard Spectra® as close as possible to the minimum recommended dose of afoxolaner and milbemycin oxime, i.e. 2.5 mg/kg body weight and 0.5 mg/kg body weight, respectively, four times at monthly intervals (Study Days 0, 28, 56 and 84) while the remaining ten dogs served as untreated controls. For parasite recovery and count, dogs were euthanized humanely and necropsied six to eight days following the last treatment (Study Days 90–92). Beginning six weeks after first inoculation, faeces were collected on a bi-weekly basis and examined for first-stage larvae of A. vasorum.ResultsUntreated dogs harboured 39–95 adult A. vasorum (geometric mean, 66.4), while zero to 24 adult A. vasorum were recovered from the treated dogs (geometric mean, 3.4; P < 0.0001). Thus, efficacy of NexGard Spectra® administered at monthly intervals against incoming A. vasorum was 94.9 %. Compared to the untreated controls, larval excretion of the treated dogs was reduced by 99.9 % (P < 0.0001).ConclusionResults of this study demonstrate that NexGard Spectra®, when administered at monthly intervals, can effectively prevent canine A. vasorum infection.

Preliminary report on the prevalence of Angiostrongylus vasorum infection in dogs from Portugal adopting a commercially available test kit for serological analysis

Canine angiostrongylosis, caused by the nematode Angiostrongylus vasorum, is an emerging and spreading disease with an increasing number of cases diagnosed in European countries in the last few years; nevertheless, little information is available in Portugal. The prevalence of A. vasorum antigens was assessed with a rapid test (Angio Detect™) in 400 dogs from four geographic areas of mainland Portugal. While an apparent prevalence of 0.0% was found, the true prevalence was estimated to lie between 0.0% and 0.3%, taking into account the non-absolute test sensitivity and specificity. Despite the low prevalence of A. vasorum infection in mainland Portugal, it will be important for veterinary clinicians to be aware of angiostrongylosis in order to consider it in the differential diagnosis of canine diseases (including cardiopulmonary dirofilariosis, caused by the heartworm Dirofilaria immitis).

Angiostrongylus-associated pneumonia in a red panda (Ailurus fulgens)

A red panda (Ailurus fulgens) within a zoological collection was noted by keepers to be acutely dyspnoeic with no apparent premonitory signs and died before intervention. Postmortem examination demonstrated severe...

A post-mortem study of respiratory disease in small mustelids in south-west England.

BackgroundStoat (Mustela erminea) and weasel (Mustela nivalis) populations in south-west England are declining whilst polecats (Mustela putorius), absent for over a century, are increasing. Little is known about the health status of these species nationally. This study aimed at investigating respiratory disease in specimens found dead in south-west England.ResultsTrauma caused by road traffic, predator attack or being trapped was the predominant cause of death in 42 stoats, 31 weasels and 20 polecats; most were in good physical condition. Skrjabingylus nasicola was present in all species (weasels 37 %, polecats 39 %, stoats 41 %) and infected animals showed no evidence of loss of body condition. Even in carcases stored frozen L1 larvae were frequently alive and highly motile. Angiostrongylus vasorum infection was diagnosed in two stoats and one weasel: in stoats infections were patent and the lung lesions were likely of clinical significance. These are believed to be the first records of A. vasorum in small mustelids. Pleuritis and pyothorax was seen in two polecats, in one case due to a migrating grass awn. Histological examination of lungs showed granulomata in stoats (38 %), weasels (52 %) and polecats (50 %). Spherules consistent with Emmonsia spp. adiaspores were present in the granulomata of stoats (60 %), weasels (36 %) and polecats (29 %). Adiaspore diameter in all three species was similar (means: stoats 39 μm, weasels 30 μm, polecats 36 μm); these are markedly smaller than that normally recorded for E. crescens. Although they lie within the accepted range for spores of Emmonsia parva this arid-zone species is not found in Britain, thus raising a question over the identity of the fungus. Cases showing numerous granulomata but few or no adiaspores were Ziehl-Neelsen-stain negative for acid-fast bacilli and IHC negative for Mycobacterium spp. However, in some cases PCR analyses revealed mycobacteria, including Mycobacterium kumamotonense and Mycobacterium avium Complex. One stoat had numerous unidentified small organisms present centrally within granulomata.ConclusionsStoats, weasels and polecats in south-west England share several respiratory diseases, often of high prevalence, but the pathology would appear insufficient to impact on the health status of the populations and other ultimate causes of death should be investigated when examining these species.

Intrapulmonary arteriovenous anastomoses in dogs with severe Angiostrongylus vasorum infection: clinical, radiographic, and echocardiographic evaluation

BackgroundIn both humans and dogs the pulmonary vasculature is able to recruit large-diameter anatomical intrapulmonary arteriovenous anastomoses (IPAVAs). In healthy people the opening of these anastomoses affects the degree of exercise-induced increase in pulmonary arterial pressure. The presence of these IPAVAs can be demonstrated using saline contrast echocardiography. ObjectivesThe aims of the present study were to characterize severely affected, naturally infected dogs with Angiostrongylus vasorum, to evaluate if these dogs can open IPAVAs, and to assess if the recruitment of such anastomoses affects the severity of pulmonary hypertension (PH). AnimalsEight client-owned dogs with severe A. vasorum infection were recruited. MethodsDogs with A. vasorum infection that presented with severe dyspnea and/or syncope were prospectively screened by echocardiography for the presence of PH and IPAVAs. Only severely affected dogs, based on a combination of clinical, radiographic and echocardiographic abnormalities, were enrolled. ResultsOpening of IPAVAs could be demonstrated in three dogs with no to moderate PH, and could not be demonstrated in five dogs with severe PH. In two dogs thoracic radiographs showed only mild interstitial changes, while computer tomography and postmortem examination revealed severe pulmonary interstitial and vascular disease. ConclusionsThese results suggest that dogs may open IPAVAs and that opening of such anastomoses may play a regulatory role in the development of PH. There may be a marked discrepancy between radiographic changes and disease severity in A. vasorum.

Detection of Angiostrongylus vasorum by quantitative PCR in bronchoalveolar lavage fluid in Belgian dogs.

To describe Angiostrongylus vasorum infection in a series of clinical cases over a 12-month period, report the use of quantitative PCR on broncho-alveolar lavage fluid and investigate the -possibility of previously undiagnosed angiostrongylosis in a retrospective cohort of coughing and healthy dogs. Pulmonary angiostrongylosis was diagnosed based on compatible clinical signs and positive quantitative PCR on broncho-alveolar lavage fluid and/or positive Baermann examination. Quantitative PCR was also performed retrospectively on broncho-alveolar lavage fluid from 65 dogs (55 coughing and 10 healthy dogs), examined between 2008 and 2014; results of Baermann examination were also available in 33 dogs. Seven young adult dogs from Southeastern Belgium with respiratory clinical signs were diagnosed with angiostrongylosis between March 2013 and April 2014. Positive broncho-alveolar lavage fluid quantitative PCR results and positive Baermann examination were obtained in 5/5 and 2/5 dogs, respectively. In the remaining two dogs, only Baermann analysis was performed. Among the retrospective cohorts, only one broncho-alveolar lavage fluid from a coughing dog was quantitative PCR-positive whereas all faecal samples were negative. Until recently, canine angiostrongylosis was not reported in Belgium. It should now be included in the differential diagnosis of coughing Belgian dogs. Identification of affected dogs may be aided by quantitative PCR on broncho-alveolar lavage fluid.

Coagulation status in dogs with naturally occurring Angiostrongylus vasorum infection.

Angiostrongylus vasorum infection is associated with bleeding tendencies in approximately one-third of clinical cases. The cause of the coagulopathy is poorly understood but may be related to disseminated intravascular coagulation. Thromboelastography is a global evaluation of coagulation and has not been described in a cohort of dogs with this disease. Thromboelastography in association with other measures of coagulation including prothrombin and activated partial thromboplastin times, antithrombin percentage activity and D-dimer and von Willebrand factor concentrations was evaluated in a group of 30 dogs with A. varosum infection. A total of 18 dogs had signs of bleeding on physical examination. Thromboelastography was consistent with hypocoagulation in 17 of these dogs. There was no association between any of the other measures and hypocoagulation on thromboelastography. Abnormal coagulation times were not significantly associated with bleeding. Only fibrinogen concentration was significantly lower in dogs that were bleeding compared with those that were not (P = 0 · 026). D-dimer concentrations were increased in 22/25 cases in the study; however, other coagulation parameters were more variable. Although the changes identified in this study were not consistent, there is activation of coagulation within this population, possibly consistent with an intravascular disseminated coagulopathy.

Retrospective evaluation of moderate-to-severe pulmonary hypertension in dogs naturally infected with Angiostrongylus vasorum.

The outcome in dogs with pulmonary hypertension associated with natural Angiostrongylus vasorum infection is unclear. This study aimed to report long-term outcome of dogs with A. vasorum and pulmonary hypertension, and to evaluate factors associated with pulmonary hypertension development. It was hypothesised that dogs with pulmonary hypertension had a shorter survival time than dogs without pulmonary hypertension. Retrospective review of clinical records of dogs diagnosed with A. vasorum. Dogs were classified as having or not having pulmonary hypertension based on clinical signs and imaging findings. Signalment, signs and outcome were recorded. DNA obtained from banked samples was genotyped for the PDE5a:E90K polymorphism, a possible factor in development of pulmonary hypertension. The proportion of dogs with moderate-to-severe pulmonary hypertension and A. vasorum infection in the study population was 14 · 6%. No difference in the population characteristics or PDE5a genotype was detected between dogs with and without pulmonary hypertension. Dogs with pulmonary hypertension had a significantly shorter survival time (P = 0 · 006) and a greater risk of death within 6 months of diagnosis (odds ratio 12 · 5, 95% confidence interval 2 · 1 to 74 · 9; P = 0 · 0053). A. vasorum-associated pulmonary hypertension is an important problem in naturally infected dogs and has a negative effect upon survival.