重症肌无力患者血清中Ryanodine受体抗体检测及其临床意义

目的　探讨Ryanodine受体 (RyR)抗体在重症肌无力 (MG)诊断中的临床意义。方法　以差速离心法提取富含RyR的肌质网 (SR)提取物 ,建立ELISA RyR抗体检测系统 ,分析 6 6例伴胸腺瘤的MG(MGT)、98例非胸腺瘤MG(NTMG)和 5 0例非重症肌无力 (NMG)及 12 3名健康人 (NC)血清中RyR抗体水平。 结果　MGT组RyR抗体阳性检出率显著性高于NTMG组和NMG组 (P <0 0 1) ,敏感性和特异性分别达 81 8%和 94 5 %。不同胸腺组织学类型MGT之间RyR抗体阳性检出率差异无显著意义 (P >0 0 5 )。RyR抗体呈阳性MG组的年龄、临床评分和乙酰胆碱受体抗体水平均显著高于RyR抗体阴性MG组 (P <0 0 1)。RyR抗体水平同MG患者临床症状的严重程度呈正相关 ,尤其是MGT组 (r =0 6 2 6 ,P <0 0 1)。不同胸腺组织学类型MGT中以上皮细胞型相关性最高 (r =0 5 92 ,P <0 0 1)。结论　RyR抗体检测对诊断MGT具有较高的敏感性和特异性 ,并且与MG患者临床症状的严重程度呈正相关。

Detection of Ryanodine receptor antibody in sera of myasthenia gravis patients and its clinical significance

Objective To evaluate the significance to detect the Ryanodine receptor (RyR) antibody in the sera of myasthenia gravis (MG) patients.Methods Sarcoplasmic reticulum abound with RyR was extracted by centrifugation,and levels of antibodies in 66 MG patients with thymoma (MGT),98 non-thymoma MG (NTMG) patients,50 non-myasthenia gravis (NMG) patients and 123 normal persons were examined by ELISA-RyR method.Results RyR antibody positive rate of MGT was the highest among MGT,NTMG and NMG groups ( P <0.01),the sensitivity was 81.8% while the speciality was 94.5%.The positive rates of MGT groups with different thymus histology had no statistic differences ( P >0.05).Ages,clinical scores and levels of acetycholine receptor antibodies of patients with RyR antibody positive sera were higher than those with RyR antibody negative sera ( P <0.01).The levels of RyR had positive correlation with the severities of MG patients,especially MGT ( r =0.626, P <0.01),and MGT with thymoma of epithelioid cells had the highest correlation coefficient ( r =0.592, P <0.01).Conclusion The detection of RyR antibody has better sensitivity and speciality in examining the MGT patients,and the levels of that antibody have positive correlation with the severities of MG patients.