[Therapeutic strategy in myasthenia gravis]

The purpose of the treatment of autoimmune myasthenia gravis is to directly improve neuromuscular transmission, and also to reduce the production or presence of the nicotinic acetylcholine receptor (achR). Acetylcholinesterase inhibitors are the first line treatment with the rapid onset of effect, for all types of myasthenia gravis (ocular, generalized myasthenia gravis, seronegative or seropositive patients). Plasmapheresis or intravenous immunoglobulin (IVIg) is the treatment for exacerbations. Their main advantage is the rapid onset of the effect. Three to five plasma exchanges or IVIg infusions (1.2 to 2 g/b.w administered over 2-5 days) are usually recommended. In case of suspected thymoma, thymectomy should be always performed. The option of thymectomy is discussed in young patients less than 50 years old with unstable myasthenia gravis, even if thymoma lesions are not suspected. Corticosteroids and/or immunosuppressive agents are used in severe forms of the disease. A few randomized studies have shown the efficacy of the therapeutic agents. Corticosteroids are considered a major treatment of myasthenia gravis but the doses and periods of time are still being debated. The combination of corticosteroids and immunosuppressive agents are recommended early to spare corticosteroids. The treatment of myasthenia gravis should be modulated regularly (minimal doses for example).