Clinical Significance of Repetitive Compound Muscle Action Potentials in Patients with Myasthenia Gravis: A Predictor for Cholinergic Side Effects of Acetylcholinesterase Inhibitors
Journal of Clinical Neurology
; : 482-488, 2016.
Article
de En
| WPRIM
| ID: wpr-104817
Bibliothèque responsable:
WPRO
ABSTRACT
BACKGROUND AND PURPOSE: Acetylcholinesterase inhibitors (AChEIs) are widely used to treat myasthenia gravis (MG). Although AChEIs are usually tolerated well, some MG patients suffer from side effects. Furthermore, a small proportion of MG patients show cholinergic hypersensitivity and cannot tolerate AChEIs. Because repetitive compound muscle action potentials (R-CMAPs) are an electrophysiologic feature of cholinergic neuromuscular hyperactivity, we investigated the clinical characteristics of MG patients with R-CMAPs to identify their clinical usefulness in therapeutic decision-making. METHODS: We retrospectively reviewed the clinical records and electrodiagnostic findings of MG patients who underwent electrodiagnostic studies and diagnostic neostigmine testing (NT). RESULTS: Among 71 MG patients, 9 could not tolerate oral pyridostigmine bromide (PB) and 17 experienced side effects of PB. R-CMAPs developed in 24 patients after NT. The highest daily dose of PB was lower in the patients with R-CMAPs (240 mg/day vs. 480 mg/day, p<0.001). The frequencies of PB intolerance and side effects were higher in the patients with R-CMAPs than in those without R-CMAPs [37.5% vs. 0% (p<0.001) and 45.8% vs. 12.8% (p=0.002), respectively]. The MG Foundation of America postintervention status did not differ significantly between MG patients with and without R-CMAPs, and the response to immunotherapy was also good in both groups. CONCLUSIONS: Side effects of and intolerance to AChEIs are more common in MG patients with R-CMAPs than in those without R-CMAPs. AChEIs should be used carefully in MG patients with R-CMAPs. The presence of R-CMAPs after NT may be a good indicator of the risks of PB side effects and intolerance.
Mots clés
Texte intégral:
1
Indice:
WPRIM
Sujet Principal:
Acetylcholinesterase
/
Bromure de pyridostigmine
/
Amériques
/
Potentiels d'action
/
Anticholinestérasiques
/
Études rétrospectives
/
Hypersensibilité
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Immunothérapie
/
Myasthénie
/
Néostigmine
Type d'étude:
Observational_studies
/
Prognostic_studies
Limites du sujet:
Humans
langue:
En
Texte intégral:
Journal of Clinical Neurology
Année:
2016
Type:
Article