Diagnostic Value of Auxiliary Examinations for New Onset Patients with Myasthenia Gravis

Objective To investigate the diagnostic value of commonly used auxiliary examinations in new onset patients with definitely diagnosed myasthenia gravis (MG). Methods A total of 156 patients were enrolled into the study who visited department of neurology of Beijing Hospital during the period from January, 1999 to December,2004 and were diagnosed as patients with MG. They had been treated with repetitive nerve stimulation (RNS), single fiber eleetromyography examination (SFEMG), neostigmine test, and acetylcholine receptor antibody (AChRAb) determination. Results The positive cases of NST, RNS, SFEMG and AChRAb for the patients with definitely diagnosed MG were 135 (86.5%), 129(82.7%), 108(69.2%), and 99(63.5%) cases respectively. There was no statistically significant difference between NST and SFEMG (P0.05). There was significant difference between the positive rate of NST and that of RNS and AChRAb (P0.05). There was significant difference between the positive rate of SFEMG and that of RNS and AChRAb (P0.05). Conclusions Combined auxiliary examinations are necessary in making clinically correct diagnosis of MG. And NST and RNS have the highest sensitivity to diagnose new onset patients with MG.