非胸腺瘤性眼外肌麻痹起病重症肌无力胸腺切除时机探讨

目的比较非胸腺瘤性眼外肌麻痹起病重症肌无力(ocular onset myasthenia gravis,OMG-O)患者于不同病程行胸腺切除后病情缓解与向全身型重症肌无力(GMG)转化的差异,以期对手术时机进行探讨。方法采用双向队列研究方法,对作者医院2005年1月至2017年9月因药物治疗效果不佳而行胸腺切除的86例OMG-O患者,按起病至手术时间间隔分为早手术组(≤1年)、晚手术组(>1年),比较两组患者不同随访时间理想状态(干预后状态达到轻微异常及更好)率、GMG转化率的差异。结果 (1)与早手术组比较,晚手术组少年MG(<18岁)比例较高,起病至手术时间间隔、起病至使用激素时间间隔、激素用药时间较长(均P <0.05)。(2)与晚手术组比较,早手术组术后第3年理想状态率高(P=0.029),而第2、4~8年理想状态率有升高趋势,但差异无统计学意义(P>0.05)。(3)9例术后发生GMG转化,起病至发生GMG转化时间中位数17.8个月,其中6例(66.7%)在3年内发生GMG转化。早手术组与晚手术组间GMG转化率比较,差异无统计学意义(12.5%比8.7%;χ~2=0.049,P=0.825)。结论对于药物治疗无效或不耐受的OMG-O患者,早期行胸腺切除手术疗效较好;但即使手术,仍有可能发生GMG转化,约1/2患者于起病后1.5年内发生,约2/3于起病后3年内发生。

A study on the timing of thymectomy in patients with ocular onset non-thymomatous myasthenia gravis

Objective To explore the most appropriate operation time for patients with ocular onset nonthymomatous myasthenia gravis(OMG-O)by comparing the remission and development of generalized MG(GMG)post thymectomy.Methods This is a retrospective and prospective cohort study.Eighty-six patients with OMG-O who underwent thymectomy from January 2005 to September 2017 due to ineffectiveness or intolerance to anticholinesterase and/or glucocorticoids were divided into early operation group(≤1 year)and late operation group(>1 year)based on the interval between onset and operation date.Their ideal state rate(ideal state means minimal manifestations or better in myasthenia gravis foundation of America postintervention status)and generalization rate of MG were compared between two groups.Results (1)The proportion of Juvenile MG(JMG,with MG onset before 18 years old)was higher,the interval between MG onset and thymectomy,between MG onset and glucocorticoid administration initiation and duration of glucocorticoids therapy were longer in the late operation group,compared with those in the early operation group(P<0.05).(2)Ideal state rate post thymectomy in the 3 rd year was higher in the early operation group than that in the late operation group(P=0.029).The ideal state rate of the 2 nd and from the 4 th to the 8 th year tended to increase in the early operation group,compared to those in late operation group,but there were no significant differences.(3)Nine patients developed to GMG after thymectomy,six cases within three years.The median interval between ocular onset and GMG was 17.8 months.Five cases(12.5%)in the early operation group and four cases(8.7%)in the late operation group developed to GMG,there were no significant differences between two groups.Conclusions It is a suitable option for patients with OMG-O to accept thymectomy at their early stage of disease,if they are ineffective or intolerable to anticholinesterase and/or glucocorticoid treatment.Development to GMG could still happen in some patients with OMG-O,even after thymectomy.About half of patients with OMG-O may progress to GMG within 1.5 years of onset and two-thirds within 3 years of onset.