Equine Protozoal Myeloencephalitis: An Updated Consensus Statement with a Focus on Parasite Biology, Diagnosis, Treatment, and Prevention.
Abstract: Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite-specific factors such as strain differences in virulence, remain largely undetermined. This consensus statement update presents current published knowledge of the parasite biology, host immune response, disease pathogenesis, epidemiology, and risk factors. Importantly, the statement provides recommendations for EPM diagnosis, treatment, and prevention.
Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Publication Date: 2016-02-09 PubMed ID: 26857902PubMed Central: PMC4913613DOI: 10.1111/jvim.13834Google Scholar: Lookup
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Summary
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Equine protozoal myeloencephalitis (EPM) is a notable neurologic disorder in horses that remains challenging to diagnose and is characterized by central nervous system problems. The disease is brought on by two main parasites and despite the identification of certain risk factors, much about the disease and its virulence remains undefined. This research paper serves as an update on our understanding of EPM, detailing the biology of the parasites, the way they interact with their hosts, and the pathogenesis and epidemiology of the disease, whilst providing recommendations for diagnosis, treatment, and prevention.
Disease Overview and Parasite Biology
- EPM is a prominent neurological disorder that affects horses and displays no specific clinical signs. Horses suffering from EPM can have a localized or widespread central nervous system (CNS) disease.
- The disease is brought about by one of two parasites, Sarcocystis neurona or Neospora hughesi. There is less information available about the latter.
Disease Diagnosis
- EPM is difficult to diagnose unless post-mortem examination is carried out. Therefore, diagnosis relies heavily on the veterinarian’s knowledge and observational skills.
Risk Factors and Disease Pathogenesis
- While certain risk factors have been pinpointed, such as stress related to transportation and correlations with particular breeds and ages, much about the biological factors contributing to the disease is still unresolved.
- Genetic predispositions of individual animals may play a role in susceptibility to EPM, as well as parasite-specific factors like variations in virulence among different strains.
Recommendations for Diagnosis, Treatment, and Prevention
- As part of this consensus statement update, the research paper details the present understanding of the biology of the parasites involved, the host immune response, the pathogenesis of the disease, and its epidemiology.
- Crucially, it also provides recommendations for diagnosing, treating, and preventing EPM, offering crucial guidance for the management of this challenging disorder in horses.
Cite This Article
APA
Reed SM, Furr M, Howe DK, Johnson AL, MacKay RJ, Morrow JK, Pusterla N, Witonsky S.
(2016).
Equine Protozoal Myeloencephalitis: An Updated Consensus Statement with a Focus on Parasite Biology, Diagnosis, Treatment, and Prevention.
J Vet Intern Med, 30(2), 491-502.
https://doi.org/10.1111/jvim.13834 Publication
Researcher Affiliations
- Rood and Riddle Equine Hospital, 2150 Georgetown Road, Lexington, Kentucky, 40511.
- Department of Veterinary Science, Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY.
- Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK.
- Department of Veterinary Science, Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY.
- New Bolton Center, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA.
- College of Veterinary Medicine, University of Florida, Gainesville, FL.
- Equine Diagnostic Solutions LLC, Lexington, KY.
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA.
- Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA.
MeSH Terms
- Animals
- Antiprotozoal Agents / therapeutic use
- Coccidiosis / drug therapy
- Coccidiosis / veterinary
- Encephalomyelitis / drug therapy
- Encephalomyelitis / parasitology
- Encephalomyelitis / veterinary
- Horse Diseases / drug therapy
- Horse Diseases / parasitology
- Horse Diseases / pathology
- Horses
- Neospora / isolation & purification
- Practice Guidelines as Topic
- Sarcocystis / isolation & purification
- Sarcocystosis / drug therapy
- Sarcocystosis / veterinary
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