Equine hyperkalemic periodic paralysis: review and implications.
Abstract: The purpose of this review is to present an up-to-date summary of the signs, diagnosis, treatment, and implications of equine hyperkalemic periodic paralysis. The review encompasses all original articles published between 1986 and early 1993. Hyperkalemic periodic paralysis is the result of a genetic mutation in the skeletal muscle sodium channel gene. It is inherited as an autosomal dominant trait; most affected horses are heterozygotes. The classical signs are muscle fasciculation, spasm, and weakness associated with hyperkalemia. However, these signs are only rarely observed in affected horses. Potential sequelae to attacks are abrasions and involuntary recumbency; these problems are not specific for hyperkalemic periodic paralysis, but they occur more frequently in hyperkalemic periodic paralysis-affected horses. It is also likely that hyperkalemic periodic paralysis results in greater muscle mass. There are suggestions that homozygotes may be more severely affected and show signs of upper respiratory obstruction as foals. The practitioner needs to be aware of the tests for hyperkalemic periodic paralysis, and their limitations, so that he can properly diagnose this condition. The industry has the difficult problem of deciding whether or not testing should be mandatory and the fate of positive horses.
Publication Date: 1994-05-01 PubMed ID: 8050073PubMed Central: PMC1686662
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- Journal Article
- Review
Summary
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The research article provides an in-depth review of equine hyperkalemic periodic paralysis (EHPP), a condition arising from a genetic mutation in horses, detailing its signs, diagnosis, and treatment, along with the ramifications of the disorder.
Overview of Equine Hyperkalemic Periodic Paralysis
- Equine Hyperkalemic Periodic Paralysis (EHPP) is a condition in horses caused by a mutation in the skeletal muscle sodium channel gene. This mutation results in episodes of muscle weaknes, spasms, and twitching, often related to high levels of potassium in the blood (hyperkalemia).
- The mutation is passed on as an autosomal dominant trait, meaning that horses can inherit the condition if one of their parents carries the gene.
- Although the typical symptoms such as muscle twitching and spasms are expected, they surprisingly occur very rarely in affected horses.
Implication and Consequences of EHPP
- EHPP can result in a series of complications including abrasions and involuntary laying down due to muscle weakness. These consequences appear more commonly in horses with EHPP when compared to those not affected.
- Another probable outcome of EHPP is an increase in muscle mass. This consequence, though potentially advantageous, is attributed to the genetic mutation.
- There are indications that horses with two copies of the mutated gene (homozygotes) may face severe symptoms that even extend to signs of upper respiratory obstruction when they are still foals.
Diagnosis and Treatment of EHPP
- Veterinary practitioners should possess an understanding of the tests for detecting EHPP, as well as their limitations, in order to accurately diagnose the condition.
- Common methods to diagnose EHPP involve blood tests to measure potassium levels and genetic testing to identify the presence of the mutation.
- Treatment often involves dietary management to control potassium levels and medications to help manage symptoms during an episode.
Challenges Facing the Industry
- One of the biggest industry challenges surrounding EHPP is deciding whether testing for this genetic mutation should be made compulsory or not.
- Moreover, there remains uncertainty about the fate of horses that test positive for the mutation.
Cite This Article
APA
Naylor JM.
(1994).
Equine hyperkalemic periodic paralysis: review and implications.
Can Vet J, 35(5), 279-285.
Publication
Researcher Affiliations
- Department of Veterinary Internal Medicine, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon.
MeSH Terms
- Animals
- Horse Diseases / diagnosis
- Horse Diseases / genetics
- Horse Diseases / physiopathology
- Horse Diseases / therapy
- Horses
- Hyperkalemia / complications
- Hyperkalemia / diagnosis
- Hyperkalemia / physiopathology
- Hyperkalemia / veterinary
- Male
- Paralysis / complications
- Paralysis / diagnosis
- Paralysis / physiopathology
- Paralysis / veterinary
References
This article includes 21 references
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Citations
This article has been cited 5 times.- Tong CW, Balakrishnan A, Wynne RM. Recurrent Hyperkalemia During General Anesthesia in a Dog. Front Vet Sci 2020;7:210.
- Husulak ML, Lohmann KL, Gabadage K, Wojnarowicz C, Marqués FJ. Equine motor neuron disease in 2 horses from Saskatchewan. Can Vet J 2016 Jul;57(7):771-6.
- Gandolfi B, Gruffydd-Jones TJ, Malik R, Cortes A, Jones BR, Helps CR, Prinzenberg EM, Erhardt G, Lyons LA. First WNK4-hypokalemia animal model identified by genome-wide association in Burmese cats. PLoS One 2012;7(12):e53173.
- Brosnahan MM, Brooks SA, Antczak DF. Equine clinical genomics: A clinician's primer. Equine Vet J 2010 Oct;42(7):658-70.
- Rollet M, Flyps J, Vernemmen I, van Loon G, Schauvliege S. Case Report: Inhaled salbutamol in the successful treatment of life-threatening acute hyperkalaemia in an anaesthetised horse. Front Vet Sci 2025;12:1663681.
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