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Sullivan JM, Aasen TL, Fisher CJ, Schaer M. Retrospective Evaluation of Clinical and Clinicopathologic Findings, Case Management, and Outcome for Dogs and Cats Exposed to Micrurus fulvius (Eastern Coral Snake): 92 Cases (2021-2022). Toxins (Basel) 2024; 16:246. [PMID: 38922141 PMCID: PMC11209501 DOI: 10.3390/toxins16060246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 04/19/2024] [Accepted: 05/21/2024] [Indexed: 06/27/2024] Open
Abstract
This retrospective, observational study describes the clinical findings, case management trends, and outcomes of 83 dogs and nine cats exposed to eastern coral snakes in a university teaching hospital setting. The medical records of dogs and cats that received antivenom following coral snake exposure were reviewed. Data collected included signalment, time to antivenom administration, physical and laboratory characteristics at presentation, clinical course during hospitalization, length of hospitalization, and survival to discharge. The mean time from presentation to coral snake antivenom administration was 2.26 ± 1.46 h. Excluding cases where the owner declined in-hospital care, the mean hospitalization time for dogs and cats was 50.8 h and 34 h, respectively. The mean number of antivenom vials was 1.29 (1-4). Gastrointestinal signs (vomiting and ptyalism) occurred in 42.2% (35/83) of dogs and 33.3% (3/9) of cats. Peripheral neurologic system deficits (ataxia, paresis to plegia, absent reflexes, and hypoventilation) were noted in 19.6% (18/92) of dogs and cats. Hemolysis was also common in 37.9% (25/66) of dogs but was not observed in cats. Mechanical ventilation (MV) was indicated in 12% (10/83) of dogs but no cats. Acute kidney injury (AKI), while rare, was a common cause of euthanasia at 20% (2/5) and was the most common complication during MV at 44.4% (4/9). Pigmenturia/hemolysis occurred in 88.9% (8/9) of MV cases and in all cases with AKI. Despite delays in antivenom administration by several hours, dogs and cats with coral snake exposure have low mortality rates (6% of dogs (5/83) and 0% of cats). Gastrointestinal signs were common but were not predictive of progression to neurological signs. Thus, differentiating between coral snake exposure and envenomation before the onset of neurological signs remains challenging.
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Affiliation(s)
| | | | | | - Michael Schaer
- Department of Small Animal Clinical Sciences, Veterinary Teaching Hospital, University of Florida, 2015 S.W. 16th Ave, Gainesville, FL 32610-0144, USA; (J.M.S.); (T.L.A.); (C.J.F.)
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Morris CAD, Donaldson RE. Mechanical ventilation in snake envenomation of dogs and cats. Front Vet Sci 2023; 10:1071257. [PMID: 37065246 PMCID: PMC10090310 DOI: 10.3389/fvets.2023.1071257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 03/14/2023] [Indexed: 03/31/2023] Open
Abstract
Envenomation by snakes in Elapidae and Viperidae families have been associated with respiratory failure in dogs and cats. Mechanical ventilation may be required for hypoventilation due to neuromuscular paralysis or hypoxemia due to pulmonary hemorrhage or aspiration pneumonia. Median incidence of dogs and cats with snake envenomation that require mechanical ventilation is 13% (0.06-40%). Standard treatment of snake envenomation in dogs and cats includes prompt administration of appropriate antivenom and management of envenomation complications such as coagulopathy, rhabdomyolysis and acute kidney injury. When mechanical ventilation is required, overall prognosis is good with appropriate treatment. Standard anesthetic protocols and mechanical ventilator settings are generally appropriate, with lung protective ventilation strategies typically reserved for patients with pulmonary disease. Median survival to discharge for cats and dogs with elapid envenomation is 72% (76-84%) with 33 h (19.5-58 h) median duration of mechanical ventilation and 140 h (84-196 h) median hospitalization. This article reviews indications for mechanical ventilation in cats and dogs with snake envenomation, and discusses ventilator settings, anesthetic and nursing considerations, complications and outcomes specific to this disease.
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Affiliation(s)
- Cameron A. D. Morris
- Critical Care Department, Queensland Veterinary Specialists, Brisbane, QLD, Australia
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Heinz JA, Mankin J, Pashmakova M. Transient Megaesophagus Following Coral Snake Envenomation in Three Dogs (2013-2018). J Am Anim Hosp Assoc 2021; 56:320. [PMID: 33113557 DOI: 10.5326/jaaha-ms-6915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2019] [Indexed: 11/11/2022]
Abstract
A 12 yr old dachshund, a 7 yr old English springer spaniel, and a 1.5 yr old French bulldog presented following envenomation by a coral snake. Each patient displayed evidence of varying degrees of lower motor neuron dysfunction, but all three developed transient megaesophagus. Two patients developed secondary aspiration pneumonia, with one requiring mechanical ventilation, which the owners declined, resulting in euthanasia. The third developed hypoventilation without aspiration pneumonia, was mechanically ventilated, and was successfully weaned. In the two surviving patients, the megaesophagus resolved by time of discharge. Coral snake envenomation is an uncommon occurrence, and these are the first documented cases of transient megaesophagus secondary to a North American species.
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Affiliation(s)
- Justin Andrew Heinz
- From Texas A&M University, College Station, Texas (J.A.H., J.M.); and BluePearl Veterinary Partners, Clearwater, Florida (M.P.)
| | - Joseph Mankin
- From Texas A&M University, College Station, Texas (J.A.H., J.M.); and BluePearl Veterinary Partners, Clearwater, Florida (M.P.)
| | - Medora Pashmakova
- From Texas A&M University, College Station, Texas (J.A.H., J.M.); and BluePearl Veterinary Partners, Clearwater, Florida (M.P.)
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Maxwell K, Fraser B, Schaer M, Allen A. A retrospective evaluation of eastern coral snake envenomation and antivenom administration in cats: 30 cases (2012-2019). Toxicon 2020; 191:38-43. [PMID: 33316296 DOI: 10.1016/j.toxicon.2020.11.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 11/19/2020] [Accepted: 11/30/2020] [Indexed: 10/22/2022]
Abstract
Thirty cats were identified to be have been suspected to have a potential coral snake envenomation after searching medical records from 2012 to 2019 at a university teaching hospital. The records were reviewed and evaluated for signalment, date and time of the snake encounter, elapsed time between encounter and hospital examination, presenting complaint, initial physical examination findings, initial laboratory findings, antivenom dose and duration of administration, adverse reactions to antivenom, additional treatments administered, progression of clinical signs, length of hospitalization, and outcome. Thirteen cats presented with clinical signs consistent with envenomation while 17 cats were treated for possible asymptomatic envenomation, as defined by the owner discovering a live or dead coral snake in their home or on their property. Initial physical examination findings included tachypnea with short shallow breaths and use of accessory muscles; tetraparesis with normal or decreased to absent spinal reflexes; cranial nerve deficits including decreased to absent gag, slow pupillary light reflexes, and absent physiologic nystagmus; and normal or altered mentation. Laboratory findings included hypercapnia, hyperglycemia, hypokalemia, increased aspartate aminotransferase activity, increased alanine aminotransferase activity, echinocytosis, leukocytosis, azotemia, and hyperlactatemia. Twenty-eight cats received antivenom; two cats received two vials while twenty-six cats received one vial. Antivenom reaction was suspected in one cat that developed facial swelling during administration of the drug. Average length of hospitalization was 1 day for cats without clinical signs and 3 days for cats with clinical signs. Twenty-nine cats survived to discharge. Due to the inclusion criteria of the study, cats euthanized on presentation or discharged without receiving antivenom may have been unintentionally excluded from the study. Diagnosis of eastern coral snake envenomation should be suspected in the cat that has acute onset of lower motor neuron neuropathy. Prognosis with treatment is considered good with 97% of cats surviving to discharge. Antivenom reaction occurred in 3.5% of administrations with none being fatal. Monitoring of hypercapnia was critical in making the decision to mechanically ventilate patients. Supportive care that includes antivenom administration, recumbency care, and mechanical ventilation if needed are the mainstays of therapy.
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Affiliation(s)
- Kathleen Maxwell
- University of Florida Small Animal Hospital, 2089 Southwest 16th Avenue, Gainesville, FL, 32608, United States.
| | - Brittney Fraser
- University of Florida Small Animal Hospital, 2089 Southwest 16th Avenue, Gainesville, FL, 32608, United States.
| | - Michael Schaer
- University of Florida Small Animal Hospital, 2089 Southwest 16th Avenue, Gainesville, FL, 32608, United States.
| | - Ashley Allen
- University of Florida Small Animal Hospital, 2089 Southwest 16th Avenue, Gainesville, FL, 32608, United States.
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Campos S, Allen-Durrance AE, Schaer M, Lynch A. Retrospective evaluation of Micrurus fulvius (Eastern coral snake) envenomation and the use of mechanical ventilation in dogs and a cat (2011-2016): 8 cases. J Vet Emerg Crit Care (San Antonio) 2019; 29:662-667. [PMID: 31625672 DOI: 10.1111/vec.12892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/18/2017] [Accepted: 11/01/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To describe the use of mechanical ventilation (MV) in the management of Eastern coral snake envenomation in 7 dogs and a cat. DESIGN Retrospective study (2011-2016). SETTING University teaching hospital. ANIMALS Seven dogs and 1 cat receiving MV for ventilatory failure secondary to Eastern coral snake envenomation. INTERVENTIONS None. MEASUREMENT AND MAIN RESULTS The medical records of 8 animals that received MV following Eastern coral snake envenomation were reviewed. Data collected included signalment, time to veterinary assessment, physical and laboratory characteristics at arrival, clinical course during hospitalization, management including antivenom administration, MV settings, duration of ventilation, length of hospitalization, cost of care, and survival to discharge. The mean ± SD age was 4 ± 3.2 years. Median (range) time to onset of clinical signs was 30 (5-240) minutes. Coral snake antivenom was administered to 7 of the 8 animals following arrival at a median (range) of 30 (5-90) minutes. All animals had progressive hypoventilation and received MV, specifically volume controlled, synchronized intermittent mandatory ventilation with pressure support. The median (range) duration of MV was 58 (25-84) hours and the median (range) duration of hospitalization was 8.2 (6-11) days. Ventilator associated complications occurred in all animals, but overall outcome was excellent with 7 of 8 surviving to discharge. No dog, but the 1 cat, had an adverse reaction to antivenom. CONCLUSIONS Ventilatory failure secondary to Eastern coral snake envenomation necessitating MV carries an excellent prognosis and is better than reported for other causes of lower motor neuron disease. Successful response to ventilation was achieved even with associated complications being common in this cohort of animals.
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Affiliation(s)
- Samantha Campos
- College of Veterinary Medicine, Small Animal Clinical Sciences, University of Florida, 2015 SW 16th Ave, Gainesville, Florida
| | - Ashley E Allen-Durrance
- College of Veterinary Medicine, Small Animal Clinical Sciences, University of Florida, 2015 SW 16th Ave, Gainesville, Florida
| | - Michael Schaer
- College of Veterinary Medicine, Small Animal Clinical Sciences, University of Florida, 2015 SW 16th Ave, Gainesville, Florida
| | - Alex Lynch
- College of Veterinary Medicine, Small Animal Clinical Sciences, North Carolina State University, Raleigh, North Carolina
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Fernández ML, Quartino PY, Arce-Bejarano R, Fernández J, Camacho LF, Gutiérrez JM, Kuemmel D, Fidelio G, Lomonte B. Intravascular hemolysis induced by phospholipases A 2 from the venom of the Eastern coral snake, Micrurus fulvius: Functional profiles of hemolytic and non-hemolytic isoforms. Toxicol Lett 2017; 286:39-47. [PMID: 29197624 DOI: 10.1016/j.toxlet.2017.11.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/10/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
Abstract
A unique feature of the venom of Micrurus fulvius (Eastern coral snake) is its ability to induce severe intravascular hemolysis in particular species, such as dogs or mice. This effect was previously shown to be induced by distinct phospholipase A2 (PLA2) isoforms which cause direct hemolysis in vitro, an uncommon finding for such enzymes. The functional profiles of PLA2-17, a direct hemolytic enzyme, and PLA2-12, a co-existing venom isoform lacking such effect, were compared. The enzymes differed not only in their ability to cause intravascular hemolysis: PLA2-17 additionally displayed lethal, myotoxic, and anticoagulant actions, whereas PLA2-12 lacked these effects. PLA2-12 was much more active in hydrolyzing a monodisperse synthetic substrate than PLA2-17, but the catalytic activity of latter was notably higher on a micellar substrate, or towards pure phospholipid artificial monolayers under controlled lateral pressures. Interestingly, PLA2-17 could hydrolyze substrate at a pressure of 20 mN m-1, in contrast to PLA2-12 or the non-toxic pancreatic PLA2. This suggests important differences in the monolayer penetrating power, which could be related to differences in toxicity. Comparative examination of primary structures and predicted three-dimensional folding of PLA2-12 and PLA2-17, revealed that differences concentrate in their N-terminal and central regions, leading to variations of the surface properties at the membrane interacting interface. PLA2-17 presents a less basic interfacial surface than PLA2-12, but more bulky aromatic residues, which could be associated to its higher membrane-penetrating strength. Altogether, these structural and functional comparative observations suggest that the ability of PLA2s to penetrate substrate interfaces could be a major determinant of toxicity, perhaps more important than protein surface charge.
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Affiliation(s)
- María Laura Fernández
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica
| | - Pablo Yunes Quartino
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Ruth Arce-Bejarano
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica
| | - Julián Fernández
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica
| | - Luis F Camacho
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica
| | - Daniel Kuemmel
- Biology and Chemistry Department, University of Osnabrueck, Osnabrueck, Germany
| | - Gerardo Fidelio
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica San José 11501, Costa Rica.
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Aird SD, da Silva NJ, Qiu L, Villar-Briones A, Saddi VA, Pires de Campos Telles M, Grau ML, Mikheyev AS. Coralsnake Venomics: Analyses of Venom Gland Transcriptomes and Proteomes of Six Brazilian Taxa. Toxins (Basel) 2017; 9:E187. [PMID: 28594382 PMCID: PMC5488037 DOI: 10.3390/toxins9060187] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 05/31/2017] [Accepted: 06/02/2017] [Indexed: 11/16/2022] Open
Abstract
Venom gland transcriptomes and proteomes of six Micrurus taxa (M. corallinus, M. lemniscatus carvalhoi, M. lemniscatus lemniscatus, M. paraensis, M. spixii spixii, and M. surinamensis) were investigated, providing the most comprehensive, quantitative data on Micrurus venom composition to date, and more than tripling the number of Micrurus venom protein sequences previously available. The six venomes differ dramatically. All are dominated by 2-6 toxin classes that account for 91-99% of the toxin transcripts. The M. s. spixii venome is compositionally the simplest. In it, three-finger toxins (3FTxs) and phospholipases A₂ (PLA₂s) comprise >99% of the toxin transcripts, which include only four additional toxin families at levels ≥0.1%. Micrurus l. lemniscatus venom is the most complex, with at least 17 toxin families. However, in each venome, multiple structural subclasses of 3FTXs and PLA₂s are present. These almost certainly differ in pharmacology as well. All venoms also contain phospholipase B and vascular endothelial growth factors. Minor components (0.1-2.0%) are found in all venoms except that of M. s. spixii. Other toxin families are present in all six venoms at trace levels (<0.005%). Minor and trace venom components differ in each venom. Numerous novel toxin chemistries include 3FTxs with previously unknown 8- and 10-cysteine arrangements, resulting in new 3D structures and target specificities. 9-cysteine toxins raise the possibility of covalent, homodimeric 3FTxs or heterodimeric toxins with unknown pharmacologies. Probable muscarinic sequences may be reptile-specific homologs that promote hypotension via vascular mAChRs. The first complete sequences are presented for 3FTxs putatively responsible for liberating glutamate from rat brain synaptosomes. Micrurus C-type lectin-like proteins may have 6-9 cysteine residues and may be monomers, or homo- or heterodimers of unknown pharmacology. Novel KSPIs, 3× longer than any seen previously, appear to have arisen in three species by gene duplication and fusion. Four species have transcripts homologous to the nociceptive toxin, (MitTx) α-subunit, but all six species had homologs to the β-subunit. The first non-neurotoxic, non-catalytic elapid phospholipase A₂s are reported. All are probably myonecrotic. Phylogenetic analysis indicates that the six taxa diverged 15-35 million years ago and that they split from their last common ancestor with Old World elapines nearly 55 million years ago. Given their early diversification, many cryptic micrurine taxa are anticipated.
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Affiliation(s)
- Steven D Aird
- Division of Faculty Affairs, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
| | - Nelson Jorge da Silva
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás 74605-140, Brazil.
| | - Lijun Qiu
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
| | - Alejandro Villar-Briones
- Research Support Division, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
| | - Vera Aparecida Saddi
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás 74605-140, Brazil.
- Laboratório de Oncogenética e Radiobiologia da Associação de Combate ao Câncer em Goiás, Universidade Federal de Goiás, Rua 239 no. 52-Setor Universitário, Goiânia, Goiás 74065-070, Brazil.
| | - Mariana Pires de Campos Telles
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás 74605-140, Brazil.
- Laboratório de Genética & Biodiversidade, Universidade Federal de Goiás, Goiânia, Goiás 74690-900, Brazil.
| | - Miguel L Grau
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
| | - Alexander S Mikheyev
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa-ken 904-0495, Japan.
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Abstract
Cases of rattlesnake envenomation in dairy goats are lacking. These cases present three dairy goats presented to a veterinary referral hospital for envenomation of Northern Pacific Rattlesnake (Crotalus oreganus). Treatments and clinical characteristics reported are similar to those for llamas, alpacas, and horses. These cases suggest that quick treatment in the event of a bite may have a more favorable clinical response. Existing rattlesnake bite scoring systems applicable to other species may be applicable to goats, and existing respiratory pathology may predispose goats to a less favorable outcome.
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Intravascular hemolysis induced by the venom of the Eastern coral snake, Micrurus fulvius, in a mouse model: Identification of directly hemolytic phospholipases A2. Toxicon 2014; 90:26-35. [DOI: 10.1016/j.toxicon.2014.07.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/14/2014] [Accepted: 07/23/2014] [Indexed: 11/18/2022]
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Sonis J, Hackett E, Callan R, Holt T, Hackett T. Prairie Rattlesnake Envenomation in 27 New World Camelids. J Vet Intern Med 2013; 27:1238-41. [DOI: 10.1111/jvim.12143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/06/2013] [Accepted: 06/05/2013] [Indexed: 11/28/2022] Open
Affiliation(s)
- J.M. Sonis
- Department of Clinical Sciences; Colorado State University; Fort Collins CO
| | - E.S. Hackett
- Department of Clinical Sciences; Colorado State University; Fort Collins CO
| | - R.J. Callan
- Department of Clinical Sciences; Colorado State University; Fort Collins CO
| | - T.N. Holt
- Department of Clinical Sciences; Colorado State University; Fort Collins CO
| | - T.B. Hackett
- Department of Clinical Sciences; Colorado State University; Fort Collins CO
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Myokymia and neuromyotonia in veterinary medicine: a comparison with peripheral nerve hyperexcitability syndrome in humans. Vet J 2013; 197:153-62. [PMID: 23583699 DOI: 10.1016/j.tvjl.2013.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/12/2013] [Accepted: 03/04/2013] [Indexed: 01/17/2023]
Abstract
Involuntary muscle hyperactivity can result from muscle or peripheral nerve hyperexcitability or central nervous system dysfunction. In humans, diseases causing hyperexcitability of peripheral nerves are grouped together under the term 'peripheral nerve hyperexcitability' (PNH). Hyperexcitability of the peripheral motor nerve can result into five different phenotypic main variants, i.e. fasciculations, myokymia, neuromyotonia, cramps and tetany, each with their own clinical and electromyographic characteristics. This review focuses on the most commonly described expressions of PNH in veterinary medicine, i.e. myokymia and neuromyotonia, in particular in young Jack Russell terriers. Data from 58 veterinary cases with generalized myokymia and neuromyotonia were analyzed, including unpublished treatment and follow-up data on eight Jack Russell terriers from a previous study and seven additional Jack Russell terriers. A dysfunction of the potassium channel or its associated proteins has been found in many human syndromes characterized by PNH, in particular in generalized myokymia and neuromyotonia, and is suspected to occur in veterinary medicine. Potential pathomechanisms of potassium channel dysfunction leading to signs of PNH are broad and include genetic mutations, antibody-mediated attack or ion channel maldistribution due to axonal degeneration or demyelination. A more accurate classification of the different PNH syndromes will facilitate a more rapid diagnosis and guide further research into natural occurring PNH in animals.
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