Brain and spinal cord haemorrhages associated with Angiostrongylus vasorum infection in four dogs

Abstract

Multifocal haemorrhages associated with Angiostrongylus vasorum infection were observed in the central nervous system of four dogs with neurological signs including depression, seizures, spinal pain and paresis. In magnetic resonance images the majority of the lesions were isointense or slightly hyperintense in T1-weighted images, hyperintense in T2-weighted images and hypointense in T2*-weighted (gradient echo) images, compatible with haemorrhages more than seven days old. Lesions were found in the brain of three of the dogs and in the spinal cord of two. The cerebrospinal fluid contained high concentrations of protein and evidence of erythrophagia. All the dogs had coagulopathy and pulmonary haemorrhage of varying severity. A vasorum larvae were detected in the faeces of each of the dogs. Neural A vasorum was confirmed at postmortem examination in two dogs.

Pathological Findings in Dogs Naturally Infected with Angiostrongylus Vasorum in Newfoundland and Labrador, Canada

“…However, presenting clinical signs can be quite variable and include anorexia, stunted growth, weight loss, weakness, depression, vomiting, collapse, lameness, subcutaneous swelling, bleeding disorders, hypercalcemia, disseminated intravascular coagulation, and neurological signs. 1,4,8,11,12,16,21,24,27,35,36 Unfortunately, in the present study the authors were unable to assess the dogs antemortem, and clinical histories in 6 of 7 infected dogs were not available. Thus, the severity of clinical signs resulting from the pathological changes observed could not be correlated to clinical disease.…”

“…30 To further complicate things, intracranial (and intraspinal hemorrhage) has been reported in untreated infected dogs. 12,35 Bleeding tendencies caused by acquired von Willebrand factor deficiency and immune-mediated thrombocytopenia have been reported in dogs in association with A. vasorum infection. 13,36 In the latter case, increased monocyte-macrophage activation and platelet consumption caused by the formation of antiplatelet antibodies secondary to A. vasorum infection was proposed as the cause of thrombocytopenia.…”

Serological Detection of Circulating Angiostrongylus vasorum Antigen- and Parasite-Specific Antibodies in Dogs from Poland

“…The epidemiology of the parasite in further eastern European countries is poorly known. Infected dogs often present with severe respiratory symptoms but atypical clinical signs indicating coagulopathies and/or neurological dysfunctions (Mason 1989;Garosi et al 2005;Gredal et al 2011;Whitley et al 2005;Wessmann et al 2006) make the diagnosis of A. vasorum infections particularly challenging. Severe symptoms with frequently fatal outcome (Staebler et al 2005;Traversa et al 2008;Denk et al 2009) may therefore occur, because animal owners often become aware only late during the infection, due to the chronic and subtle course of the pathological processes.…”

Combined Serological Detection of Circulating Angiostrongylus vasorum Antigen and Parasite-specific Antibodies in Dogs from Hungary

“…The adult parasite lives in the pulmonary arteries and right cardiac ventricle of dogs, foxes and other wild carnivores, which are infected through the ingestion of obligatory intermediate hosts (snails or slugs) (Guilhon and Bressou 1960;Guilhon and Cens 1973) or paratenic hosts (Bolt et al 1993) containing the infectious third stage larvae. Clinical signs in dogs most frequently include respiratory signs such as coughing and dyspnoea, but a broad range of further signs indicating coagulopathies or neurological dysfunctions (Chapman et al 2004;Staebler et al 2005;Wessmann et al 2006;Koch and Willesen 2009), may be the signs most obvious to clinicians and animal owners. This variability and the fact that the disease is often in an advanced stage when noticed by the animal owners make the diagnosis of A. vasorum infections challenging but important: the sooner an appropriate anthelmintic treatment is initiated, the better for the clinical recovery of the dogs and limitation of damage, especially to lung tissues (Dennler et al 2011;Schnyder et al 2009).…”