PMID- 23720161
OWN - NLM
STAT- MEDLINE
DCOM- 20140107
LR  - 20131029
IS  - 1097-4598 (Electronic)
IS  - 0148-639X (Linking)
VI  - 48
IP  - 5
DP  - 2013 Nov
TI  - Muscle-specific kinase antibodies: a novel cause of peripheral nerve 
      hyperexcitability?
PG  - 819-23
LID - 10.1002/mus.23907 [doi]
AB  - INTRODUCTION: Antibodies that target the postsynaptic neuromuscular junction 
      (NMJ) protein, muscle-specific kinase (MuSK), have been associated with 
      myasthenia gravis (MG), often with cramps and fasciculations, after 
      administration of acetylcholinesterase inhibitors (AChE-I). METHODS: In this 
      report, 2 patients are described with elevated MuSK antibodies and evidence of 
      peripheral nerve hyperexcitability (PNH) unrelated to AChE-I medication. RESULTS: 
      Patient 1 presented with facial neuromyotonia and fasciculations, without overt 
      weakness. EMG studies demonstrated myokymic discharges in facial muscles, with 
      bursts of discharges after voluntary activation, and widespread fasciculation 
      potentials in limb muscles. Patient 2 presented with bulbar weakness and 
      fasciculations in the tongue and limbs, initially diagnosed as bulbar-onset 
      amyotrophic lateral sclerosis. Subsequent investigation identified the presence 
      of MuSK antibodies. CONCLUSIONS: We hypothesize that MuSK antibodies may induce 
      these phenotypes through disruptive actions at the NMJ, in particular the binding 
      of acetylcholinesterase (AChE) to MuSK via its collagen Q (ColQ) tail, producing 
      a reduction in synaptic AChE activity.
CI  - Copyright (c) 2013 Wiley Periodicals, Inc.
FAU - Simon, Neil G
AU  - Simon NG
AD  - Department of Neurology, University of California San Francisco, San Francisco, 
      California, USA.
FAU - Reddel, Stephen W
AU  - Reddel SW
FAU - Kiernan, Matthew C
AU  - Kiernan MC
FAU - Layzer, Robert
AU  - Layzer R
LA  - eng
PT  - Case Reports
PT  - Journal Article
DEP - 20130626
PL  - United States
TA  - Muscle Nerve
JT  - Muscle & nerve
JID - 7803146
RN  - 0 (Autoantibodies)
RN  - 0 (Receptors, Cholinergic)
RN  - EC 2.7.10.1 (MUSK protein, human)
RN  - EC 2.7.10.1 (Receptor Protein-Tyrosine Kinases)
RN  - EC 3.1.1.7 (Acetylcholinesterase)
SB  - IM
MH  - Acetylcholinesterase/metabolism
MH  - Autoantibodies/metabolism/*physiology
MH  - Electromyography
MH  - Facial Muscles/enzymology/innervation
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Muscle, Skeletal/enzymology/innervation
MH  - Neuromuscular Junction/*enzymology/immunology
MH  - Peripheral Nervous System Diseases/*enzymology/*immunology/physiopathology
MH  - Receptor Protein-Tyrosine Kinases/*immunology
MH  - Receptors, Cholinergic/*immunology
MH  - Synaptic Transmission/immunology
MH  - Tongue/enzymology/innervation
OTO - NOTNLM
OT  - MuSK
OT  - fasciculations
OT  - myasthenia gravis
OT  - neuromyotonia
OT  - peripheral nerve hyperexcitability
EDAT- 2013/05/31 06:00
MHDA- 2014/01/08 06:00
CRDT- 2013/05/31 06:00
PHST- 2013/05/13 00:00 [accepted]
PHST- 2013/05/31 06:00 [entrez]
PHST- 2013/05/31 06:00 [pubmed]
PHST- 2014/01/08 06:00 [medline]
AID - 10.1002/mus.23907 [doi]
PST - ppublish
SO  - Muscle Nerve. 2013 Nov;48(5):819-23. doi: 10.1002/mus.23907. Epub 2013 Jun 26.