Low frequency repetitive nerve stimulation in anti-muscle specific tyrosine kinase receptor antibody positive myasthenia gravis / 中华神经科杂志

ABSTRACT

Objective To describe the repetitive nerve stimulation ( RNS) in anti-muscle specific tyrosine kinase (anti-MuSK) receptor antibody positive myasthenia gravis (MG), and compare with anti-acetylcholine receptor ( AChR ) positive myasthenia gravis , to figure out characteristics of anti-MuSK receptor MG.Methods We analyzed clinical and RNS data of nine anti-MuSK receptor MG and 19 age-and sex-matched anti-AChR MG.RNS was performed to the abductor digiti minimi , orbicularis oculi or musculus frontalis and trapezius .Results In anti-MuSK receptor MG , abnormal RNS in facial nerve was seen in 6/9 and in trapezius was 5/9, in limbs was 0.In anti-AChR MG, abnormal RNS in facial nerve was seen in 13/19, in trapezius was 18/19 and in limbs was 7/19.Abnormal in any of three parts was 8/9 and 19/19 in anti-MuSK receptor MG and anti-AChR MG, respectively.The RNS decrementing was more obvious in facial nerve in anti-Musk receptor MG than in anti-AChR MG.Negative prostigmin test was independently associated with anti-MuSK receptor MG (OR=4.25,95% CI 2.19 -15.25, P=0.015). Conclusions Abnormal RNS in any of three parts is more pronounced in anti-AChR MG compared with anti-MuSK receptor MG.RNS decrementing in facial nerve is more obvious in anti-AChR MG.Negative prostigmin test can aid in early suspicion in anti-MuSK receptor MG.