Neuromyotonia in a horse

• Published in: Journal of veterinary internal medicine Vol. 33; no. 1; pp. 287 - 291
• Main Authors: Zakia, Luiza Stachewski, Palumbo, Mariana Isa Pocci, Teixeira, Raffaella Bertoni Cavalcanti, Resende, Luiz Antônio Lima, Soares, Mauro Pereira, de Oliveira‐Filho, José Paes, Amorim, Rogério Martins, Borges, Alexandre Secorun
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.01.2019; Wiley
• Subjects: Animals; Case Report; Continuous fibers; Electromyography; Electromyography - veterinary; EQUID; equine; Horse Diseases - diagnosis; Horse Diseases - pathology; Horse Diseases - physiopathology; Horses; Isaacs Syndrome - diagnosis; Isaacs Syndrome - pathology; Isaacs Syndrome - physiopathology; Isaacs Syndrome - veterinary; Membrane Glycoproteins; Muscle contraction; Muscle, Skeletal - pathology; Muscle, Skeletal - physiopathology; Muscles; myokymia; myopathy; Receptors, Interleukin-1; stiffness; myokymia; stiffness; myopathy; electromyography; equine
• ISSN: 0891-6640; 1939-1676
• DOI: 10.1111/jvim.15353

This article describes the clinical and electromyographic findings of neuromyotonia in a 19‐month‐old male crossbred Quarter Horse that presented with stiffness and muscle asymmetry in the hind limbs as well as sacrococcygeal, paravertebral, and gluteal myokymia. An electromyographic study showed spontaneous continuous muscle fiber activity with high‐frequency discharges, fibrillations, positive sharp waves, fasciculation potentials, and complex repetitive discharges. Histological examination of the gluteal muscle showed a mixed neurogenic and myopathic pattern. The findings are consistent with neuromyotonia.