重症肌无力行胸腺切除术后合并视神经脊髓炎1例

重症肌无力（myasthenia gravis,MG）和视神经脊髓炎（neuromyelitis optica,NMO）均为较少见的神经系统自身免疫性疾病,且两病极少在同一个体先后出现。首都医科大学宣武医院神经内科收治1例重症肌无力患者行胸腺切除术后4个月合并视神经脊髓炎患者,现报道如下。     

胸腺切除术后重症肌无力复发或疗效不佳的危险因素

重症肌无力(MG)是一类以自身抗体所介导、发生在神经-肌肉接头处、以部分或全部骨骼肌波动性无力为表现的自身免疫性疾病。MG患者大多数合并胸腺异常,包括胸腺增生和胸腺瘤。目前认为异常胸腺是MG患者自身抗体产生的重要场所,切除异常胸腺是治疗MG的有效手段,甚至有报道切除正常的胸腺,也会改善MG患者肌无力症状。然而,关于胸腺切除术后MG复发的报道越来越多,原因尚不明确。目前研究发现患者发病年龄、病程、美国MG基金会(MGFA)分型、胸腺病理类型、Masaoka分级、是否合并其他自身免疫性疾病等因素均可能影响胸腺切除术后MG复发或疗效不佳。     

视神经脊髓炎谱系疾病全身表现分析及其机制探讨

目的研究视神经脊髓炎谱系疾病合并中枢神经系统以外受累脏器或组织的免疫学改变。方法回顾分析56例视神经脊髓炎谱系疾病患者(视神经脊髓炎33例、非视神经脊髓炎23例)临床资料,逐一记录是否合并其他自身免疫性疾病,并行血清免疫学检测。结果视神经脊髓炎患者伴桥本甲状腺炎2例,以及系统性红斑狼疮和干燥综合征、哮喘、甲状腺功能亢进、风湿性关节炎和虹膜睫状体炎各1例。血清免疫学指标异常检出率较高者分别为甲状腺功能异常(10/17例)、抗核抗体阳性(14/28例)和补体C3阳性(8/19例),2例于分娩后发病。结论视神经脊髓炎谱系疾病患者可合并多种自身免疫性疾病,同时存在多种自身抗体,可能与视神经脊髓炎谱系疾病的发病有关。此外,妊娠期或分娩可能加重患者病情。     

重症肌无力患者胸腺瘤内Titin、Ryanodine受体表位表达

目的 研究重症肌无力（MG）患者血清连接素抗体（Titin—ab）和Ryanodine受体抗体（RyR—ab）的水平，并探讨胸腺瘤内Titin、RyR表位的表达。方法 应用ELISA法检测62例MG患者血清中Titin—ab、RyR—ab水平，以45例非MG的其他神经系统疾病患者和50名健康志愿者为对照组，采用免疫组织化学技术，对19例合并胸腺异常者[9例MG合并胸腺瘤（MGT）、6例MG合并胸腺增生（MGH）、2例MG合并胸腺萎缩（MGA）以及2例非MG胸腺癌（NMGTC）]的冰冻胸腺组织进行Titin、RyR染色。结果ELISA法显示，MG患者Titin—ab总阳性率为35．5％（22／62），其中以MGT组阳性率最高（82．3％，14／17）；而RyR—ab阳性率为24．2％（15／62），也以MGT组阳性率最高（76．5％，13／17）。9例MGT的肿瘤上皮细胞中有7例存在Titin表位的膜表达和胞质内表达，有6例存在RyR表位的膜表达；而MGH组、MGA组、NMGTC组和对照组均无阳性表达。结论 Titin—ab和RyR—ab主要见于MGT患者。MGT肿瘤上皮细胞存在Titin、RyR表位的表达。MGT患者体内Titin—ab和RyR—ab很可能是胸腺瘤内微环境的改变激活Titin、RyR特异性T细胞，致敏Titin、RyR表位使其发生自身鱼疳反廊的结果．     

视神经脊髓炎谱系疾病合并重症肌无力的临床特点及相关机制

目的探讨视神经脊髓炎谱系疾病(neuromyelitis optica spectrum disorder,NMOSD)与重症肌无力(myasthenia gravis,MG)共病的临床特点及可能机制。方法对北京协和医院炎性脱髓鞘疾病临床研究队列中的NMOSD与MG共病患者2例进行报道,并进行文献复习,总结NMOSD合并MG患者的临床特点。结果自2011年1月至2019年4月,本队列共登记NMOSD患者654例,其中2例(3.06‰)合并MG;结合既往文献报道,本文共纳入79例NMOSD与MG共病患者。NMOSD与MG共病多见于青中年,女性居多(64例,85.3%);MG多先于NMOSD发生,两病出现的平均间隔时间为(12.05±5.04)年;MG类型多为全身型(55例,69.6%),共48例(60.8%)接受了胸腺切除术;NMOSD与MG共病者可合并其他免疫疾病及存在其他免疫相关抗体阳性。结论NMOSD及MG的共病不仅仅是巧合,其共病存在一定特点,值得临床注意。     

伴胸腺瘤重症肌无力发病机制研究进展

重症肌无力(myasthenia gravis,MG)是以胸腺为靶器官的器官特异性自身免疫性疾病,伴胸腺瘤MG与不伴胸腺瘤MG发病机制不同。近年来发现伴胸腺瘤MG在T细胞数量和功能、自身抗体的种类以及遗传学等方面与不伴胸腺瘤MG存在差异。本文旨在结合文献从胸腺微环境、T细胞发育、自身抗体及遗传学等方面在伴胸腺瘤MG发病机制中作用进行综述。     

胸腺切除对重症肌无力患者T淋巴细胞亚型的影响

目的：观察胸腺切除(Tx)术对重症肌无力(MG)病人的临床疗效及对T淋巴细胞亚型的影响。方法：用许氏评分法观察30例伴胸腺增生或胸腺瘤的MG患者的病情严重程度及Tx术后2个月的临床疗效;采用直接免疫荧光染色和流式细胞仪技术测定60名志愿健康者和30例伴胸腺增生或胸腺瘤的MG患者Tx术前及术后2个月T淋巴细胞亚型的变化。结果：伴胸腺增生或胸腺瘤的MG病人Tx术前外周血中CD4＋T淋巴细胞的百分率较正常人显著增多(P＜0．01),CD8＋T淋巴细胞的百分率较正常人显著减少(P＜0．01),CD4＋/CD8＋T细胞的比例明显增高(P＜0．01)。伴胸腺增生MG病人Tx术后随着临床症状的改善,CD8＋T淋巴细胞的百分率较术前显著升高(P＜0．05),CD4＋/CD8＋T细胞的比例较术前显著下降(P＜0．05)。伴胸腺瘤MG病人Tx术后随着临床症状的改善,CD4+T淋巴细胞的百分率较术前显著下降(P＜0．05),CD4＋/CD8＋T细胞的比例较术前显著下降(P＜0．05)。结论：重症肌无力患者T淋巴细胞亚型的测定既可以为MG免疫病理学的发病机理的研究提供实验依据,也能为Tx治疗MG提供一个客观的实验室指标,为判断疾病的转归提供实验依据。     

重症肌无力胸腺淋巴细胞亚群表型的变化

目的　研究重症肌无力 (myastheniagravis ,MG)患者胸腺的T、B淋巴细胞亚群表型 ,并分析与其外周血的相关性。方法　应用免疫荧光标记技术 ,经流式细胞仪分析 ,检测了 59例MG患者 ,包括 30例伴胸腺病变患者外周血的淋巴细胞亚群表型。另外 ,对 8例MG患者的胸腺和外周血经体外培养后进行检测。结果　 ( 1)MG患者外周血辅助性T细胞 (Th ,CD4 )异常增高 ,病程 6个月以内、伴胸腺增生者Th细胞均明显增多 ;( 2 )MG胸腺和外周血中经乙酰胆碱受体 (AChR)刺激后活化的Th细胞 (CD4 CD2 5 )、CD5-B细胞 (CD5- CD19 )明显增多 ,且外周血CD5-B细胞与自身血清乙酰胆碱受体抗体 (AChRAb)滴度显著相关 (P <0 .0 1) ,胸腺摘除术 (Tx)后 ,MG外周血CD4 CD2 5 、CD5- CD19 细胞均有所减少。结论　MG患者胸腺存在着异常的AChR特异应答性T、B淋巴细胞亚群表型 ,尤其以活化的Th细胞为著 ;CD5-B细胞的产生可能与MG密切相关。     

HLA-DRB1基因型与多发性硬化易患性的关系

目的：探讨HLA基因型与多发性硬化（MS）易患者的关系。以及临床表现与基因型的关系。方法：30例MS患者（包括2对双生子患者）、40名健康对照组，应用序列特异性引物聚合酶链反应（PCR－SSP）方法进行HLA－DRB1基因分型，对2个双生子家系进行家系分析。结果：单卵双生子？（经遗传标记确定）同患MS，病变均累及大脑，脑干和脊髓，基因型为HLA－DRB1＊09＊14．1。异卵双生子之一为复发缓解型视神经脊髓炎，基因型为DRB1＊01＊12，其未患病双生子妹妹为DRB1＊17＊12。根据病变部位。30例MS中视神经脊髓炎型和西方型各15个。脊髓（70．0％），和视神经（56．7％）是最常见病变累及部位。DR15的等位基因频率在MS组无显著增高，但DR12等位基因频率在MS中显著升高（10／30vs 4/40,P=0.0157)，分层分析显示视神经脊髓炎患者中DR12等位基因频率升高，差异有极显著意义（8／15vs 4/40,P=0.0019,RR=5.33)。结论：单卵双生子与异卵双生子的患病一致性差异表明，遗传因素在MS发病中起一定作用。DR12可能是部分视神经脊髓炎型MS的易患基因，关联基因的差异可能是东西方MS临床表现和病变部位不同的原因之一。     

电压门控钾离子通道复合物抗体相关临床综合征合并伴胸腺瘤的重症肌无力患者2例及文献复习

目的探讨电压门控钾离子通道复合物(VGKCc)抗体相关临床综合征合并伴胸腺瘤的重症肌无力(MG)患者的临床特点及转归。方法回顾分析山东大学齐鲁医院(青岛)分别于2020年9月和12月收治的2例确诊为VGKCc抗体相关临床综合征合并伴胸腺瘤的MG患者, 总结其临床及辅助检查、随访预后等资料, 并结合相关文献进行复习总结。结果例1为64岁女性, 临床表现为认知障碍、精神异常和癫痫样发作, 血清富亮氨酸胶质瘤失活蛋白1(LGI1)抗体阳性, 明确诊断为抗LGI1脑炎, 既往存在球部起病的MG, 胸部CT提示胸腺瘤, 入院后给予免疫治疗后症状改善。例2为67岁男性, MG诊断明确, 后期出现认知功能下降、肌颤搐、自主神经症状, 神经电生理可见F波后放电及肌颤搐电位, 血清接触蛋白相关蛋白2抗体阳性, 明确诊断为莫旺综合征合并伴胸腺瘤的MG, 入院后给予免疫治疗及胸腺瘤切除等治疗, 症状改善。结论 VGKCc抗体相关临床综合征合并胸腺瘤的MG患者同时存在两类疾病各自的临床特点, 同时又有交叉。免疫治疗及针对胸腺瘤的治疗通常能取得较好的疗效。     

Neuromyelitis optica in patients with myasthenia gravis who underwent thymectomy

BACKGROUND: Myasthenia gravis (MG) and neuromyelitis optica (NMO, also known as Devic disease) are rare autoimmune disorders, with upper-limit prevalence estimates in the general population of 15 per 100,000 and 5 per 100,000, respectively. To our knowledge, an association between these diseases has not been previously reported. OBJECTIVES: To describe 4 patients with MG who developed NMO after thymectomy and to analyze possible causes of apparent increased prevalence of NMO among patients with MG. DESIGN: Case series. PATIENTS: Four patients with MG who underwent thymectomy. INTERVENTIONS: None. RESULTS: The prevalence of MG within the published cohort of patients with NMO is more than 150 times higher than that in the general population. CONCLUSION: Dysregulation of B-cell autoimmunity in myasthenia, possibly exacerbated by loss of control over autoreactive cells as a result of thymectomy, may predispose patients to the development of NMO.     

Altered thymic endocrine activity along with impairments of peripheral zinc metabolism and T-lymphocyte populations are associated with myasthenia gravis: a follow-up study

Thymic endocrine activity was assessed by a bioassay to determine the basal activity of thymulin (TH), a zinc dependent hormone, and its in vitro reactivation in two different age groups of patients with myasthenia gravis (MG). Before thymectomy, basal TH plasma levels were increased in patients over the age of 50 years. Plasma zinc levels were increased in all patients, this increment being very high in old patients. One year after thymectomy both TH and zinc plasma levels decreased. While zinc plasma levels were within the normal ranges for their respective ages, TH levels were lower in young and higher in old patients than in age comparable controls. Young patients with MG showed increased CD3,DR positive peripheral T-cells as well as lymphocytes with the CD16,CD56 phenotype. An increment of CD3 positive cells along with CD4 and CD16,CD56 positive cells were found in older patients. Thymectomy partially affected blood lymphocyte representation only in young patients, since CD3,DR T-cells decreased one year after surgery. No significant variations in T-cell representation were found in old patients after thymectomy. Immunosuppression in thymectomized patients did not significantly affected TH and zinc plasma levels. Very high levels of TH and the presence of additional alterations in T-lymphocyte subsets in old patients suggested that differential age related pathogenetic immunological mechanisms might be associated with the disease.     

Immunogenetic heterogeneity and associated autoimmune disorders in myasthenia gravis: a population-based survey in the province of Ferrara, northern Italy

Introduction - The well-established relationship between myasthenia gravis (MG) and HLA antigens varies among different ethnic groups. In Caucasians B8 and/or DR3 alleles have been found associated with young MG women without thymoma and with high titres of acetylcholine-receptor antibody (AChR Ab). An increased frequency of haplotype HLA-A3, B7 and/or DR2 has been observed in older MG patients with low AChR Ab levels. So far, there is no convincing evidence for an association between a specific haplotype HLA and ocular MG or MG with thymoma. MG subjects often show other concurrent autoimmune disorders suggesting a more general inherited predisposition to autoimmunity. We performed a community-based study to verify the HLA-A, B, C, DR and DQ profile on ethnically homogeneous MG patients and with the aim to estimate the frequency of concurrent autoimmune diseases and to compare HLA phenotypes to autoimmune status in different MG patients groups. Methods - Forty-seven patients, living in the province of Ferrara, were followed-up in our neurologic department and typed for HLA Antigens. In addition a set of immunological laboratory tests was performed. Results - We found a trend towards an increased B8 and DR3 frequencies in total affected population; an association between B8 allele and early onset of generalized MG sustained by thymic hyperplasia. The DR3 allele is statistically associated with the presence of additional autoimmune disorders. Conclusions - Our data support the hypothesis of a genetically-based heterogeneity of the disease and show an increased prevalence of associate autoimmune conditions in MG patients.     

Myasthenia gravis and HLA antigens in American blacks and other races

The association of HLA B8 and DR3 with generalised adult onset myasthenia gravis (GMG) in European Caucasoids is now well established. Studies of the HLA association with myasthenia gravis (MG) in other races might help to determine the location of a critical disease locus. Some previous studies in Japanese, Thais, Asian Indians and Filipinos have been reported. In this study HLA A, B, C and DR typing on 28 American blacks with either GMG or ocular myasthenia gravis (OMG) is reported. A significant increase in both HLA A1 and B8 was detected but there was an increase in DR5 rather than DR3. A review of the HLA antigen frequencies in other races and in D-penicillamine (D-Pen) induced MG suggests that prior claims implicating immune response genes marked by DR3 require review. It seems unlikely that any particular HLA allele is involved directly. Other possibly relevant combinations of alleles or supratypes are suggested. These may provide the basis for future studies of the immunogenetic basis for MG.     

Coexistence of myasthenia gravis and serological markers of neurological autoimmunity in neuromyelitis optica

We systematically evaluated the frequency of neurological disorders and muscle and neural autoantibodies in 177 patients with neuromyelitis optica (NMO) and in 250 control subjects (173 healthy; 77 multiple sclerosis, MS, patients). An excess of myasthenia gravis (MG, 2%), and muscle‐type acetylcholine receptor antibody (11%) was detected among NMO patients. The presence of neural or muscle autoantibodies was more common in NMO patients (34%) than in MS patients or healthy controls (7%), P < 0.0001. The coexistence of NMO and MG should be considered in atypical or refractory presentations of either disorder. © 2008 Wiley Periodicals, Inc. Muscle Nerve 39: 87–90, 2009     

Concomitant autoimmunity in myasthenia gravis--lack of association with IgA deficiency

A marked increase in concomitant autoimmune diseases has previously been noted in patients with myasthenia gravis (MG). We show that these diseases occur both before and after the onset of MG and that the process is not influenced by thymectomy. IgA deficiency (IgAD), which is strongly associated with the same HLA haplotype as early onset MG, has recently been suggested to be an autoimmune disease. However, there was no increase in the prevalence of IgAD in a large cohort of Swedish MG patients.     

视神经脊髓炎患者的甲状腺功能、抗体改变及并发自身免疫性甲状腺病的分析

目的 探讨37例视神经脊髓炎(NMO)患者甲状腺功能及自身抗体的改变,分析并发自身免疫性甲状腺病(AITD)的NMO患者的临床特点.方法 回顾性分析2006～2011年首都医科大学宣武医院收治的37例视神经脊髓炎患者的甲状腺功能( TSH、T3、T4、FT3、FT4)和自身甲状腺抗体(TPOAb、TGAb),38名健康体检者作为对照组,比较2组研究对象的甲状腺功能和自身甲状腺抗体有无差异.同时比较并发AITD的NMO患者(5例)与无AIDT的NMO患者(32例)的临床特征、脊髓磁共振检查结果.结果 (1)NMO组病人TSH、T3、FT3、T4和FT4与健康对照组之间差异无统计学意义;NMO组病人甲状腺自身抗体TPOAb、TGAb均高于健康对照组,两组之间差异有统计学意义(P值均＜0.05).(2)5例(13.5％)并发AITD的NMO患者发病与第一次复发间隔的时间和第一次发作的EDSS评分,与无AITD的NMO患者之间的差异有统计学意义(P值均＜0.05),而两组病人病程持续时间、发作次数、第一年复发阳性率、脊髓MRI病变节段数之间的差异均无统计学意义.结论 NMO患者的甲状腺功能正常,自身甲状腺抗体升高.并发AITD的NMO患者首次发作较轻,发病与首次复发间隔长,但不影响患者临床的总体病程.     

Linkage of HLA to myasthenia gravis and genetic heterogeneity depending on anti-titin antibodies.

BACKGROUND: MG is an autoimmune disease of the neuromuscular junction. MG with thymus hyperplasia has been associated with, but not genetically linked to, the HLA-DR3 haplotype. OBJECTIVE: To re-evaluate the association of HLA with MG in 656 patients with generalized disease and to test linkage of HLA to MG with thymus hyperplasia. METHOD: Patients were genotyped for HLA-DRB1. Data analysis included case-control comparisons after subgrouping patients by thymus histopathology. The transmission of parental alleles to MG offspring with thymus hyperplasia was studied in simplex families using the transmission/disequilibrium test (TDT) as a test of linkage. RESULTS: MG with thymus hyperplasia was positively associated with DR3 (OR = 4.5, p = 1 x 10(-6)) and negatively associated with DR7 (OR = 0.28, p = 1 x 10(-6)), based on both case-control comparisons and TDT. No association was detected with thymomas. Conversely, patients who lacked thymus anomalies but expressed anti-titin antibodies (ATA) had an increase of DR7 (OR = 2.08, p = 4 x 10(-3)) and a decrease of DR3 (OR = 0.33, p = 9 x 10(-3)). CONCLUSIONS: The authors established linkage of HLA to MG and thymus hyperplasia, defining the MYAS1 locus. Moreover, DR3 and DR7, or closely linked genes, have opposing effects on MG phenotypes. Nonthymomatous patients with ATA may be a pathogenetically distinct subset of MG patients.     

Identification of genomic typing of non-DR3 HLA class II genes associated with myasthenia gravis

HLA association with myasthenia gravis (MG) has been studied in a series of 114 patients using class I and class II genotyping after PCR amplification. Positive association was found with DR3, particularly in women (RR=2.6) and in early MG onset (RR=3.4). DRB1, DRB3, DQB1, DQA1 and B (B8 and B18_genotyping revealed that the association was predominantly with the B8 DRB1^*03 DRB3^*0101 DQB1^*0201 DQA1^*0501 ancestral haplotype. This haplotype frequency was also increased in patients with thymic hyperplasia (RR=3.5) and was greatly reduced in patients with thymona (RR=0.35). Sixteen out of 48 patients carrying this 8.1 ancestral haplotype showed absence of B8 (n=4) or of DR3 (n=12). HLA class II genotyping further revealed the existence of two other significant associations. MG was positively associated with the DQB1^*0604 allele (RR=3.4), particularly in patients with thymona (RR=5.7). Furthermore, the disease was negatively associated with DR1 in females (RR=0.32). These data suggest that MG is placed under the control of at least three distinct genes: (1) a class II predisposing gene in the 8.1 ancestral haplotype; (2) a thymona-associated class II allele on the DQB1^*0604 haplotype; and (3) a protective allele DR1.     

Neuromyelitis optica following thymectomy with severe spinal cord atrophy after frequent relapses for 30 years

A 60-year-old woman had frequent relapses of neuromyelitis optica (NMO) for 30 years despite receiving steroid and azathioprine therapy. She developed MGFA Class IIIb type of myasthenia gravis (MG) at the age of 23, and thymectomy resulted in complete remission of MG. The initial symptoms of NMO, including headache, high fever, retrobulbar optic neuritis, and neurogenic bladder, appeared at the age of 30. Two years later, paraplegia also developed. Although she received oral administration of steroids or azathioprine and intravenous steroid pulse therapy for treatment of NMO for over 30 years, she experienced frequent relapses. The examination at the ages of 58 and 60 years showed that anti-aquaporin-4 antibody was absent. Intravenous immunoglobulin therapy administered in January and June 2009 was effective, and she had 2 years of remission of NMO attack. Spinal MRI after frequent NMO attacks for 30 years revealed an extended spinal cord atrophy involving the lower cervical region and the entire thoracic region. We describe and discuss the prognosis of NMO and the effectiveness of therapies in an NMO patient who underwent thymectomy for MG.