Chan Koon Ho, Lachance Daniel H, Harper C Michel, Lennon Vanda A
Department of Laboratory Medicine & Pathology, Mayo Clinic, College of Medicine, 200 First Street S.W., Rochester, Minnesota 55905, USA.
Muscle Nerve. 2007 Nov;36(5):651-8. doi: 10.1002/mus.20854.
We determined the prevalence of muscle acetylcholine receptor (AChR) antibodies in patients with adult-acquired generalized myasthenia gravis (MG), the seroconversion rate at 12 months, and the prevalence of muscle-specific tyrosine kinase (MuSK) antibody among persistently seronegative patients. We identified 562 consecutive Mayo Clinic patients with MG based on clinical and electrophysiological criteria. At presentation, 508 patients (90.4%) tested positive for AChR binding or AChR modulating antibodies. After 12 months, 15.2% of initially seronegative patients had become seropositive, yielding a seronegativity rate of 8.2% (95% confidence interval: 6.2-9.6%). Among seronegative patients not receiving immunosuppressants, 38% were MuSK antibody-positive and 43% were seropositive for nonmuscle autoantibodies. Classification as seronegative MG should be reserved for nonimmunosuppressed patients with generalized MG who lack muscle AChR binding, AChR modulating, or MuSK antibodies at presentation and at follow-up of at least 12 months.
我们确定了成人获得性全身型重症肌无力（MG）患者肌肉乙酰胆碱受体（AChR）抗体的患病率、12个月时的血清转化速率以及持续血清阴性患者中肌肉特异性酪氨酸激酶（MuSK）抗体的患病率。我们根据临床和电生理标准，连续纳入了梅奥诊所的562例MG患者。就诊时，508例患者（90.4%）的AChR结合抗体或AChR调节抗体检测呈阳性。12个月后，15.2%最初血清阴性的患者转为血清阳性，血清阴性率为8.2%（95%置信区间：6.2 - 9.6%）。在未接受免疫抑制剂治疗的血清阴性患者中，38%为MuSK抗体阳性，43%的非肌肉自身抗体检测呈阳性。血清阴性MG的分类应仅用于未接受免疫抑制治疗、患有全身型MG且在就诊时以及至少12个月的随访中缺乏肌肉AChR结合抗体、AChR调节抗体或MuSK抗体的患者。
