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Neuromuscular Junction Disorders

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Pediatric Electromyography

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Abstract

Pediatric neuromuscular junction disorders are less common in children compared to adults, but both autoimmune and inherited subtypes of this disease category occur in the pediatric age group. Neuroanatomically, these can either be classified into presynaptic, synaptic or postsynaptic disorders. Symptoms occur when there is a disruption in the normal synthesis, storage, or release of acetylcholine, the microanatomy of the synapse, the acetylcholinesterase enzyme, or the function of the acetylcholine receptor complex. The specific clinical manifestations are dependent on the pathophysiology and severity of the disorder. The hallmarks of neuromuscular junction disorders are weakness and fatiguability, especially with extraocular muscles and bulbar muscles. However, due to the rarity of the condition and the overlap of the major symptoms with other neuromuscular or metabolic disorders, making the diagnosis can be quite challenging, from first conception of the possibility to confirmatory testing, especially as several of the classic diagnostic tests have limitations with regard to sensitivity. It is also frequently difficult to differentiate these disorders from one another, especially in children. Electrodiagnostic studies can be a valuable tool in not only detecting the presence of a disorder involving the neuromuscular junction, but also differentiating the type of neuromuscular disorders using a combination of nerve conduction studies, repetitive stimulation studies, exercise testing and needle EMG. Single fiber EMG and stimulated single fiber EMG are techniques that are also valuable in these evaluations. The results can then aid the pediatric neurologist in selecting the appropriate serologies or genetic tests to help confirm a definitive diagnosis in these patients.

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Author information

Authors and Affiliations

  1. SBCC Baby and Child Clinic, Neurology Centre, Singapore, Singapore

    Wendy K. M. Liew M.B.Ch.B., M.R.C.P.C.H., F.A.M.S

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  1. Wendy K. M. Liew M.B.Ch.B., M.R.C.P.C.H., F.A.M.S
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Correspondence to Wendy K. M. Liew M.B.Ch.B., M.R.C.P.C.H., F.A.M.S .

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Editors and Affiliations

  1. Division of Neurology, Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario, Canada

    Hugh J. McMillan

  2. Division of Pediatric Neurology, Shands Children’s Hospital, University of Florida College of Medicine, Gainesville, Florida, USA

    Peter B. Kang

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Liew, W.K.M. (2017). Neuromuscular Junction Disorders. In: McMillan, H., Kang, P. (eds) Pediatric Electromyography. Springer, Cham. https://doi.org/10.1007/978-3-319-61361-1_21

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  • DOI: https://doi.org/10.1007/978-3-319-61361-1_21

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