Investigating the clinical and laboratory characteristics of Myasthenia gravis patients and the frequency of other autoimmune diseases accompanying

Introduction and Objective: Myasthenia gravis is an autoimmune disease characterized by muscle weakness which can increase with fatigue or be partially restored with rest that is caused by antibodies to the acetylcholine receptors in the neuromuscular junction. It is known that the possibility of a second autoimmune disease in patients with autoimmune disease is higher than in the normal population. We aimed to investigate the clinical, laboratory and sociodemographic characteristics of our patients with myasthenia gravis in our clinic, to identify the most common autoimmune diseases that accompany myasthenia gravis disease and to investigate the features of myasthenia gravis patients with additional autoimmune disease. The control group was compared with MG patients. Results: 104 at 159 MG patients' autoantibody results were obtained. 159 MG patients were aged between 16-94 (mean 50.65) and 92 female and 67 male and were followed up between 2007-2017. For this reason, an autoimmune disease evaluation was performed on 104 patients. In the control group conisting of 157 patients, no difference was observed in terms of age and gender. In our study, autoimmune disease was observed in 46% (48 patients) of 104 MG patients and in 16.6% (26 patients) of 157 patients in the control group. The most common autoimmune disease is; Hashimoto's disease as seen in 31.7% (33 patients) of MG patients compared to 12.7% (20 patients) in the control group. Besides MG, 8 patients had graves disease, 3 patients had SLE, 3 patients had sjören's syndrome, 2 patients had autoimmune gastritis, 2 patients had ankylosing spondylitis and other rare autoimmune diseases. MG patients with accompanying autoimmune diseases are more generalized MG group. Autoimmune disease accompanying MG disease; showed no statistically significant differences in female gender, early onset MG and AChR antibody positive cases although it was more frequent in early onset MG and AChR antibody positive cases. Conclusion: There are many studies and case reports in the literature that have examined other autoimmune diseases accompanying MG. In the majority of these studies, the most common autoimmune disease has been shown to be hastimoto and secondly graves disease. It is notable that the frequency of additional autoimmune diseases and hashimoto disease in MG patients is higher in our study than found in the literature. Serologic examination of thyroid functions and thyroid autoantibodies, regardless of clinical findings in MG patients, will enable prevention of future hypothyroidism or hyperthyroidism and prevent clinical worsening. Other autoimmune diseases may also be asymptomatic at baseline, for this reason this should be taken into consideration when following MG patients and should be followed up with a multidisciplinary approach.