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Sarcocystis neurona encephalitis in a dog
A J Cooley1, B Barr, D Rejmanek
1College of Veterinary Medicine, Mississippi State University, Starkville, MS, USA. cooley@cvm.msstate.edu
Veterinary Pathology
|November 28, 2007
Summary
A dog diagnosed with Sarcocystis neurona encephalitis, a rare condition, showed neurological decline despite initial treatment. This case highlights Sarcocystis neurona as a potential cause of fatal encephalitis in dogs.
Area of Science:
- Veterinary Neurology
- Parasitology
- Infectious Diseases
Background:
- Sarcocystis neurona is a protozoan parasite known to cause neurological disease primarily in horses.
- Aberrant hosts for Sarcocystis neurona have been identified, but its role in canine encephalitis was previously undocumented.
Observation:
- A 1.5-year-old male Feist dog presented with hind limb paresis, progressing to recumbency and hyperesthesia.
- Initial treatment with dexamethasone provided temporary relief, but neurological signs recurred and worsened.
Findings:
- Post-mortem examination revealed multifocal encephalitis in the cerebrum and cerebellum with protozoa consistent with Sarcocystis sp.
- Immunohistochemistry and PCR confirmed the presence of Sarcocystis neurona, with strongly positive staining and genetic identification.
- Toxoplasma gondii and Neospora caninum were ruled out through serological testing.
Implications:
- This case documents Sarcocystis neurona encephalitis for the first time in a canine patient.
- It expands the known host range and clinical presentations of Sarcocystis neurona infections.
- Highlights the importance of considering Sarcocystis neurona in the differential diagnosis of canine encephalitis with neurological deficits.
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