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EMG: decremental response of compound muscle action potential to repetitive nerve stimulation

MedGen UID:
892749
Concept ID:
C4021728
Finding
Synonyms: EMG: decrement at repetitive stimulation; EMG: decremental response of CMAP to repetitive nerve stimulation
 
HPO: HP:0003403

Definition

A compound muscle action potential (CMAP) is a type of electromyography (EMG). CMAP refers to a group of almost simultaneous action potentials from several muscle fibers in the same area evoked by stimulation of the supplying motor nerve and are recorded as one multipeaked summated action potential. This abnormality refers to a greater than normal decrease in the amplitude during the course of the investigation. [from HPO]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVEMG: decremental response of compound muscle action potential to repetitive nerve stimulation

Conditions with this feature

Familial infantile myasthenia
MedGen UID:
140751
Concept ID:
C0393929
Disease or Syndrome
Congenital myasthenic syndromes (CMS) are a group of inherited disorders affecting the neuromuscular junction (NMJ). Patients present clinically with onset of variable muscle weakness between infancy and adulthood. These disorders have been classified according to the location of the defect: presynaptic, synaptic, and postsynaptic. CMS6 is an autosomal recessive CMS resulting from a presynaptic defect; patients have onset of symptoms in infancy or early childhood and tend to have sudden apneic episodes. Treatment with acetylcholinesterase inhibitors may be beneficial (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Myasthenia, limb-girdle, autoimmune
MedGen UID:
331795
Concept ID:
C1834635
Disease or Syndrome
Neuronopathy, distal hereditary motor, type 7A
MedGen UID:
322474
Concept ID:
C1834703
Disease or Syndrome
Autosomal dominant distal hereditary motor neuronopathy-7 (HMND7) is a neurologic disorder characterized by onset in the second decade of progressive distal muscle wasting and weakness affecting the upper and lower limbs and resulting in walking difficulties and hand grip. There is significant muscle atrophy of the hands and lower limbs. The disorder is associated with vocal cord paresis due to involvement of the tenth cranial nerve (summary by Barwick et al., 2012). For a general phenotypic description and a discussion of genetic heterogeneity of autosomal dominant distal HMN, see HMND1 (182960).
Congenital myasthenic syndrome 4C
MedGen UID:
373251
Concept ID:
C1837091
Disease or Syndrome
Congenital myasthenic syndrome associated with AChR deficiency is a disorder of the postsynaptic neuromuscular junction (NMJ) clinically characterized by early-onset muscle weakness with variable severity. Electrophysiologic studies show low amplitude of the miniature endplate potential (MEPP) and current (MEPC) resulting from deficiency of AChR at the endplate. Patients with mutations in the CHRNE gene may have compensatory increased expression of the fetal subunit CHRNG (100730) and may respond to treatment with cholinergic agents, pyridostigmine, or amifampridine (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Neuronal intranuclear inclusion disease
MedGen UID:
355075
Concept ID:
C1863843
Disease or Syndrome
Neuronal intranuclear inclusion disease (NIID) is an autosomal dominant, slowly progressive neurodegenerative disorder characterized by a wide range of clinical manifestations, including pyramidal and extrapyramidal symptoms, cerebellar ataxia, cognitive decline and dementia, peripheral neuropathy, and autonomic dysfunction. The age at onset varies, but most individuals present as adults between about 30 and 70 years of age. Pathologic investigation shows eosinophilic intranuclear inclusions in almost all cell types, including neurons, skin cells, fibroblasts, and skeletal muscle. Brain imaging shows a characteristic leukoencephalopathy with high intensity signals in the corticomedullary junction on diffusion-weighted imaging (DWI), as well as white matter abnormalities in subcortical and brainstem regions. Skin biopsy combined with brain imaging is useful for diagnosis (summary by Sone et al., 2016). The phenotype in some cases is suggestive of Parkinson disease (see 168600) and/or Alzheimer disease (see 104300), consistent with an evolving phenotypic spectrum of adult-onset NIID (summary by Tian et al., 2019).
Congenital myasthenic syndrome 5
MedGen UID:
400481
Concept ID:
C1864233
Disease or Syndrome
Congenital myasthenic syndromes (CMS) are a group of inherited disorders affecting the neuromuscular junction. Patients present clinically with onset of variable muscle weakness between infancy and adulthood. These disorders have been classified according to the location of the defect: presynaptic, synaptic, and postsynaptic. Endplate acetylcholinesterase deficiency is an autosomal recessive congenital myasthenic syndrome characterized by a defect within the synapse at the neuromuscular junction (NMJ). Mutations in COLQ result in a deficiency of acetylcholinesterase (AChE), which causes prolonged synaptic currents and action potentials due to extended residence of acetylcholine in the synaptic space. Treatment with ephedrine may be beneficial; AChE inhibitors and amifampridine should be avoided (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 16
MedGen UID:
481742
Concept ID:
C3280112
Disease or Syndrome
Congenital myasthenic syndrome is a disorder characterized by variable degrees of muscle fatigability caused by impaired transmission of electrical signals at the neuromuscular junction (NMJ) (summary by Arnold et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 12
MedGen UID:
765249
Concept ID:
C3552335
Disease or Syndrome
Congenital myasthenic syndrome-12 is an autosomal recessive neuromuscular disorder characterized by onset of proximal muscle weakness in the first decade. EMG classically shows a decremental response to repeated nerve stimulation. Affected individuals show a favorable response to acetylcholinesterase (AChE) inhibitors (summary by Senderek et al., 2011). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 13
MedGen UID:
766559
Concept ID:
C3553645
Disease or Syndrome
Congenital myasthenic syndrome-13 (CMS13) is an autosomal recessive neuromuscular disorder characterized by onset of proximal muscle weakness in the first decade. EMG classically shows a decremental response to repeated nerve stimulation. Affected individuals show a favorable response to acetylcholinesterase (AChE) inhibitors (summary by Belaya et al., 2012). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 8
MedGen UID:
815069
Concept ID:
C3808739
Disease or Syndrome
Congenital myasthenic syndromes are genetic disorders of the neuromuscular junction (NMJ) that are classified by the site of the transmission defect: presynaptic, synaptic, and postsynaptic. CMS8 is an autosomal recessive disorder characterized by prominent defects of both the pre- and postsynaptic regions. Affected individuals have onset of muscle weakness in early childhood; the severity of the weakness and muscles affected is variable (summary by Maselli et al., 2012). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 15
MedGen UID:
864033
Concept ID:
C4015596
Disease or Syndrome
Congenital myasthenic syndrome-15 is one of a heterogeneous group of disorders that arise from impaired signal transmission at the neuromuscular synapse and are characterized by fatigable muscle weakness (summary by Cossins et al., 2013). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 14
MedGen UID:
864034
Concept ID:
C4015597
Disease or Syndrome
Congenital myasthenic syndrome-14 is an autosomal recessive neuromuscular disorder characterized by onset of limb-girdle muscle weakness in early childhood. The disorder is slowly progressive, and some patients may become wheelchair-bound. There is no respiratory or cardiac involvement. Treatment with anticholinesterase medication may be beneficial (summary by Cossins et al., 2013). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 19
MedGen UID:
897962
Concept ID:
C4225235
Disease or Syndrome
Congenital myasthenic syndrome-19 (CMS19) is an autosomal recessive disorder resulting from a defect in the neuromuscular junction, causing generalized muscle weakness, exercise intolerance, and respiratory insufficiency. Patients present with hypotonia, feeding difficulties, and respiratory problems soon after birth, but the severity of the weakness and disease course is variable (summary by Logan et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 11
MedGen UID:
902189
Concept ID:
C4225367
Disease or Syndrome
Congenital myasthenic syndrome associated with AChR deficiency is a disorder of the postsynaptic neuromuscular junction (NMJ) clinically characterized by early-onset muscle weakness with variable severity. Electrophysiologic studies show low amplitude of the miniature endplate potential (MEPP) and current (MEPC) resulting from deficiency of AChR at the endplate. Treatment with cholinesterase inhibitors or amifampridine may be helpful (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 9
MedGen UID:
895641
Concept ID:
C4225368
Disease or Syndrome
Congenital myasthenic syndrome associated with AChR deficiency is a disorder of the postsynaptic neuromuscular junction (NMJ) clinically characterized by early-onset muscle weakness with variable severity. Electrophysiologic studies show low amplitude of the miniature endplate potential (MEPP) and current (MEPC) resulting from deficiency of AChR at the endplate. Patients may show a favorable response to amifampridine (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 4B
MedGen UID:
904424
Concept ID:
C4225369
Disease or Syndrome
Fast-channel congenital myasthenic syndrome (FCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the AChR channel, specifically from abnormally brief opening and activity of the channel, with a rapid decay in endplate current and a failure to reach the threshold for depolarization. Treatment with pyridostigmine or amifampridine may be helpful; quinine, quinidine, and fluoxetine should be avoided (summary by Sine et al., 2003 and Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 3A
MedGen UID:
898378
Concept ID:
C4225372
Disease or Syndrome
Slow-channel congenital myasthenic syndrome (SCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the AChR channel, specifically from prolonged opening and activity of the channel, which causes prolonged synaptic currents resulting in a depolarization block. This is associated with calcium overload, which may contribute to subsequent degeneration of the endplate and postsynaptic membrane. Treatment with quinine, quinidine, or fluoxetine may be helpful; acetylcholinesterase inhibitors and amifampridine should be avoided (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 2C
MedGen UID:
903254
Concept ID:
C4225373
Disease or Syndrome
Congenital myasthenic syndrome associated with AChR deficiency is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized clinically by early-onset muscle weakness with variable severity. Electrophysiologic studies show low amplitude of the miniature endplate potential (MEPP) and current (MEPC) resulting from deficiency of AChR at the endplate. Treatment with cholinesterase inhibitors or amifampridine may be helpful (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 2A
MedGen UID:
908185
Concept ID:
C4225374
Disease or Syndrome
Slow-channel congenital myasthenic syndrome (SCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the acetylcholine receptor channel, specifically from prolonged opening and activity of the channel, which causes prolonged synaptic currents resulting in a depolarization block. This is associated with calcium overload, which may contribute to subsequent degeneration of the endplate and postsynaptic membrane. Treatment with quinine, quinidine, or fluoxetine may be helpful; cholinesterase inhibitors and amifampridine should be avoided (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 17
MedGen UID:
895078
Concept ID:
C4225377
Disease or Syndrome
Any congenital myasthenic syndrome in which the cause of the disease is a mutation in the LRP4 gene.
Myasthenic syndrome, congenital, 1B, fast-channel
MedGen UID:
909200
Concept ID:
C4225405
Disease or Syndrome
Fast-channel congenital myasthenic syndrome (FCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the acetylcholine receptor (AChR) channel, specifically from abnormally brief opening and activity of the channel, with a rapid decay in endplate current and a failure to reach the threshold for depolarization. Treatment with pyridostigmine or amifampridine may be helpful; quinine, quinidine, and fluoxetine should be avoided (summary by Sine et al., 2003 and Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myasthenic syndrome 4A
MedGen UID:
908188
Concept ID:
C4225413
Disease or Syndrome
Slow-channel congenital myasthenic syndrome (SCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the acetylcholine receptor channel, specifically from prolonged opening and activity of the channel, which causes prolonged synaptic currents resulting in a depolarization block. This is associated with calcium overload, which may contribute to subsequent degeneration of the endplate and postsynaptic membrane. Treatment with quinine, quinidine, or fluoxetine may be helpful; acetylcholinesterase inhibitors and amifampridine should be avoided (summary by Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Myasthenic syndrome, congenital, 25, presynaptic
MedGen UID:
1683288
Concept ID:
C5193027
Disease or Syndrome
Congenital myasthenic syndrome-25 (CMS25) is an autosomal recessive neuromuscular disorder characterized by hypotonia and generalized muscle weakness apparent from birth. Affected individuals have feeding difficulties and delayed motor development, usually never achieving independent ambulation. Additional variable features include eye movement abnormalities, joint contractures, and rigid spine. Pyridostigmine treatment may be partially effective (summary by Shen et al., 2017). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462).
Congenital myopathy with reduced type 2 muscle fibers
MedGen UID:
1672638
Concept ID:
C5193081
Disease or Syndrome
Congenital myopathy-14 (CMYP14) is an autosomal recessive skeletal muscle disorder characterized by onset of severe muscle weakness apparent at birth and sometimes in utero. Affected infants have difficulty breathing independently and usually require mechanical ventilation for variable lengths of time. Other features include delayed motor development with delayed walking, hypo- or areflexia, and high-arched palate. Skeletal muscle biopsy shows variation in fiber size with specific atrophy of the fast-twitch type II fibers. Cardiac muscle is not affected (summary by Ravenscroft et al., 2018). For a discussion of genetic heterogeneity of congenital myopathy, see CMYP1A (117000).
Myopathy, epilepsy, and progressive cerebral atrophy
MedGen UID:
1759100
Concept ID:
C5436652
Disease or Syndrome
Myopathy, epilepsy, and progressive cerebral atrophy (MEPCA) is a severe autosomal recessive disorder with onset in utero or at birth. Affected individuals have hypotonia with respiratory or feeding difficulties apparent from birth and often associated with contractures of the large joints. There is little spontaneous movement: skeletal muscle biopsy and electrophysiologic studies are consistent with a myopathy or myasthenic disorder. Patients also develop refractory seizures with burst-suppression pattern or hypsarrhythmia on EEG. Brain imaging shows progressive cerebral atrophy and myelination defects. All patients reported to date died within the first year of life (summary by Schorling et al., 2017).
Myasthenic syndrome, congenital, 7B, presynaptic, autosomal recessive
MedGen UID:
1794157
Concept ID:
C5561947
Disease or Syndrome
Autosomal recessive presynaptic congenital myasthenic syndrome-7B (CMS7B) is characterized by severe generalized muscle weakness apparent from birth; decreased fetal movements may be apparent in utero. Affected infants have generalized hypotonia with poor cry and feeding, head lag, and facial muscle weakness with ptosis. Some patients may have respiratory involvement. Electrophysiologic studies show decreased compound muscle action potentials (CMAPs) and a decremental response to repetitive nerve stimulation. Treatment with 3,4-diaminopyridine and pyridostigmine may result in clinical improvement (summary by Bauche et al., 2020).
Combined oxidative phosphorylation deficiency 58
MedGen UID:
1841277
Concept ID:
C5830641
Disease or Syndrome
Combined oxidative phosphorylation deficiency-58 (COXPD58) is an autosomal recessive disorder characterized by a wide range of clinical presentations including neonatal lactic acidosis, epileptic encephalopathy, developmental delay and impaired intellectual development with nonspecific changes on brain MRI, or mitochondrial myopathy with a treatable neuromuscular transmission defect (Van Haute et al., 2023). For a discussion of genetic heterogeneity of combined oxidative phosphorylation deficiency, see COXPD1 (609060).

Professional guidelines

PubMed

Kongsaengdao S, Samintarapanya K, Rusmeechan S, Sithinamsuwan P, Tanprawate S
Muscle Nerve 2009 Aug;40(2):271-8. doi: 10.1002/mus.21256. PMID: 19609915

Recent clinical studies

Etiology

Hu F, Jin J, Kang L, Jia R, Qin X, Liu X, Liu X, Liu C, Wang L, Zhang R, Dang J
Eur Neurol 2018;80(3-4):151-156. Epub 2018 Nov 21 doi: 10.1159/000494670. PMID: 30463071
Miyaji Y, Hatanaka Y, Higashihara M, Kanbayashi T, Tanaka F, Sonoo M
Clin Neurophysiol 2018 Feb;129(2):345-348. Epub 2017 Nov 21 doi: 10.1016/j.clinph.2017.11.007. PMID: 29288989
Gurnett CA, Bodnar JA, Neil J, Connolly AM
J Child Neurol 2004 Mar;19(3):175-82. PMID: 15119478
Sanmuganathan PS
Postgrad Med J 1998 Oct;74(876):596-9. doi: 10.1136/pgmj.74.876.596. PMID: 10211352Free PMC Article

Diagnosis

Hu F, Jin J, Kang L, Jia R, Qin X, Liu X, Liu X, Liu C, Wang L, Zhang R, Dang J
Eur Neurol 2018;80(3-4):151-156. Epub 2018 Nov 21 doi: 10.1159/000494670. PMID: 30463071
Jing F, Cui F, Chen Z, Yang F, Ling L, Huang X
Eur Neurol 2015;74(1-2):22-7. Epub 2015 Jul 1 doi: 10.1159/000431284. PMID: 26138989
Kongsaengdao S, Samintarapanya K, Rusmeechan S, Sithinamsuwan P, Tanprawate S
Muscle Nerve 2009 Aug;40(2):271-8. doi: 10.1002/mus.21256. PMID: 19609915
Michel P, Sternberg D, Jeannet PY, Dunand M, Thonney F, Kress W, Fontaine B, Fournier E, Kuntzer T
Muscle Nerve 2007 Nov;36(5):643-50. doi: 10.1002/mus.20856. PMID: 17654559
Gutierrez AR, Bodensteiner J, Gutmann L
J Child Neurol 1994 Oct;9(4):362-5. doi: 10.1177/088307389400900404. PMID: 7822724

Therapy

Kongsaengdao S, Samintarapanya K, Rusmeechan S, Sithinamsuwan P, Tanprawate S
Muscle Nerve 2009 Aug;40(2):271-8. doi: 10.1002/mus.21256. PMID: 19609915
Gurnett CA, Bodnar JA, Neil J, Connolly AM
J Child Neurol 2004 Mar;19(3):175-82. PMID: 15119478
Singh G, Pannu HS, Chawla PS, Malhotra S
Muscle Nerve 1999 Dec;22(12):1637-43. doi: 10.1002/(sici)1097-4598(199912)22:12<1637::aid-mus4>3.0.co;2-a. PMID: 10567075
Triggs WJ, Beric A, Butler IJ, Roongta SM
Muscle Nerve 1992 Mar;15(3):267-72. doi: 10.1002/mus.880150302. PMID: 1313543
Maselli R, Jacobsen JH, Spire JP
Ann Neurol 1986 May;19(5):508-10. doi: 10.1002/ana.410190517. PMID: 3717911

Prognosis

Gurnett CA, Bodnar JA, Neil J, Connolly AM
J Child Neurol 2004 Mar;19(3):175-82. PMID: 15119478

Clinical prediction guides

Hu F, Jin J, Kang L, Jia R, Qin X, Liu X, Liu X, Liu C, Wang L, Zhang R, Dang J
Eur Neurol 2018;80(3-4):151-156. Epub 2018 Nov 21 doi: 10.1159/000494670. PMID: 30463071
Miyaji Y, Hatanaka Y, Higashihara M, Kanbayashi T, Tanaka F, Sonoo M
Clin Neurophysiol 2018 Feb;129(2):345-348. Epub 2017 Nov 21 doi: 10.1016/j.clinph.2017.11.007. PMID: 29288989
Jing F, Cui F, Chen Z, Yang F, Ling L, Huang X
Eur Neurol 2015;74(1-2):22-7. Epub 2015 Jul 1 doi: 10.1159/000431284. PMID: 26138989
Wadman RI, Vrancken AF, van den Berg LH, van der Pol WL
Neurology 2012 Nov 13;79(20):2050-5. Epub 2012 Oct 31 doi: 10.1212/WNL.0b013e3182749eca. PMID: 23115209
Triggs WJ, Beric A, Butler IJ, Roongta SM
Muscle Nerve 1992 Mar;15(3):267-72. doi: 10.1002/mus.880150302. PMID: 1313543

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