Autoantibodies, clinical phenotypes and quality of life in Lebanese patients with myasthenia gravis.

Myasthenia gravis (MG) is a rare autoimmune disease that affects the neuromuscular junction. It is characterized by the production of heterogeneous autoantibodies that bind to the neuromuscular junction and alter neural transmission. Recently, more attention was given to MG-related antibodies and their clinical influence. In Lebanon, studies about MG are very rare. To date, there is still no research on the different autoantibodies developed by Lebanese MG patients. We conducted a study aimed at detecting the prevalence of different antibodies in a group of seventeen Lebanese patients with MG, and exploring their associations with clinical phenotypes and quality of life (QOL). MG antibody test in Lebanon is restricted only to two antibodies: acetylcholine receptor (anti-AChR) and muscle-specific kinase (anti-MUSK) antibodies. Results showed that 70.6% of patients were anti-AChR positive and all of them were anti-MUSK negative. Association between MG serological profiles, clinical outcomes and QOL was not significant. Together, current findings suggest that anti-MUSK antibody is not common and difference in antibody profile may not change the clinical phenotypes and QOL of MG Lebanese patients. In the future, it is recommended to check also for autoantibodies other than anti-AChR and anti-MUSK, which may reveal new antibody profiles and possible associations with clinical outcomes.