AChR-Ab And MuSK-Abin Myasthenia Gravis

Objective：By detecting the serum concentrations of AChR-Ab andMuSK-Ab in myasthenia gravis patients, To explore the correlationsbetween the the serum concentrations of AChR-Ab, MuSK-Ab in peripheralblood and Osserman classification and Pathological histology of thymus inpatients who with MG.Methods:1This study is divided into myasthenia gravis group and healthy controls.Myasthenia Gravis (MG) group,33patients with MG, were hospitalizedpatients in neurology and thoracic surgery in the second hospital of hebeimedical university from December2011to December2012.All patients werediagnosed with myasthenia gravis standards:There is abnormal skeletal musclefatigue phenomenon, morning light sunset heavy, Neostigmine test positive,Repetitive nerve stimulation at low frequency band to reduce more than15%.On CT examination of thymus,23patients was normal,10patients withthymus abnormal (thymus hyperplasia, thymoma, etc.) transferred to thethoracic surgery, to thymectomy, routine pathologic examination of thethymus.By pathologic examination of the thymus,6patients were thymushyperplasia and4patients were thymoma. In33patients, male21cases,12cases were female, aged from22to77years, the median age of58years.According to Osserman classification, patients of MG were divided intoOcular group and Generalized group. There were11cases in the Oculargroup,22cases in the generalized group.Healthy controls (the health control,HC) group included20cases.8casesamong them were female,12cases were male, aged from44to75years, themedian age of56years.2Serum specimen sampling and storage①T ake4ml fasting blood within24hours from33in-hospital MG patients.②Take4ml blood on an empty stomach in the morning from20cases ofhealthy controls.③All specimens be placed more than1hour at room temperature.④U sing high-speed centrifuge centrifuge specimens at a speed of3000r/min for10minutes.⑤Pipetting the upper serum, repackaging in sequence in four0.5ml ofEP tube.⑥Indicatting the number.⑦s tored in-80℃refrigerator.To reduce error, a unified testing is required.3Test specimensUsing enzyme-linked immunosorbent (ELISA) method to detect the MGgroup and HC group patients AChR-Ab, MuSK-Ab concentration.Results:1Average concentration of AChR-Ab in MG group (33cases) was (0.777±0.248)ng/ml, significantly higher than that of HC group (0.305±0.105)ng/ml.The difference was statistically significant (P＜0.05).2Average concentration of AChR-Ab in Ocular group (11cases)was（0.795±0.285） ng/ml, generalized group was (0.768±0.289) ng/ml.Comparing the two groups there was no statistically significant difference.(P＞0.05).3The average concentration of AChR-Ab in normal group (23cases) was（0.764±0.333） ng/ml; Thymus hyperplasia group (6cases) was（0.688±0.066） ng/ml; Thymus gland tumor group (4cases) was（0.899±0.139）ng/ml. Comparing the three groups there were not statisticalsignificance differences (P＞0.05).4The specificity of AChR-Ab by Elisa detectting to the diagnosis ofmyasthenia gravis was85%, sensitivity was84.8%5Average MuSK-Ab concentration of MG group was（0.311±0.126）ng/ml as well as HC group was（0.272±0.121）ng/ml, there is no obvious difference.(P＞0.05).6Average MuSK-Ab concentration of Ocular group was (0.259±0.079)ng/ml, the generalized group of MuSK-Ab concentration was (0.337±0.139)ng/ml, Compared with the two groups, there was no evident difference.(P＞0.05).7The MuSK-Ab concentration of thymus normal group was（0.343±0.127）ng/ml, that in thymus hyperplasia group was（0.260±0.100）ng/ml, and that in thymus gland tumor group （0.204±0.081）ng/ml. There isno obvious difference among the3groups.(P＞0.05).8MuSK-Ab Concentration of AChR-Ab negative group was（0.442±0.112）ng/ml, significantly higher than that of AChR-Ab positivegroup（0.281±0.113）ng/ml, the difference was statistically significant (P＜0.05).9MuSK-Ab on myasthenia gravis diagnostic specificity was90%, with9.1%sensitivity and60%sensitivity was to AChR-Ab negative group.Conclusions:1Enzyme-linked immunosorbent (ELISA) method to detect AChR-Abindex can be used as a reference for clinical diagnosis of myasthenia gravis.2AChR-Ab concentration has no obvious relation to the severity ofclinical symptoms.3The MuSK-Ab serum AChR-Ab negative myasthenia gravis has goodsensitivity, can be detected in patients with serum AChR-Ab negative usingthis indicator.4The MuSK-Ab positive cases appeared only in the patients with thymusnormal. There is no proof that this antibody is associated with lesions in thethymus.