Myasthenia Gravis

Overview of myasthenia gravis is a nerve-muscle joint position for acetylcholine receptor and reduce obstacles to the transfer emerged own immune disease. The main clinical features of local or systemic rhabdomyosarcoma in activities easily fatigue weakness, After a rest or anti-esterase bulbs alkaline substances can be mitigated. Also involved cardiac and smooth muscle, showing the corresponding visceral symptoms. Pathology Disease in recent years under the ultrastructure, the study found that The disease is mainly postsynaptic membrane acetylcholine receptor (AChR) of lesions. Electron microscopic examination see endplate of the presynaptic nerve endings in the number and diameter vesicles not changed, but the synaptic gap broadens, postsynaptic membrane fold lighter little will change, and therefore the postsynaptic membrane area and acetylcholine receptor numbers. The use of electric eels discharge organ extraction and purification, the acetylcholine receptor as the antigen and adjuvant mixed immunization in the rabbit, monkey, rat, in the second pay antigen injection, could result in experimental autoimmune myasthenia gravis model and the animals were detected in the serum anti-acetylcholine receptor antibody (anti Serum). Clinical about 85% serum can be detected in anti AchRab. But with the antibody concentration is not necessarily a serious condition parallel line. A recent study showed that the plasma of patients with IgG blocked the AChR sodium channels. This also explains some of the anti-Serum-negative patients the pathogenesis. Many clinical phenomena suggest disease and disorders of the immune mechanism. About 70% of the cases are thymus hyperplasia, and the emergence lymphocytes germinal center; Another 15% in patients with thymoma. In addition, patients often accompanied by her other autoimmune diseases. The sick part of the serum, can be found in anti-nuclear, anti-skeletal muscle, anti thymus, thyroid cells, and other anti-antibody and rheumatoid factor. Common muscle biopsy lymphocytes assembly kitchen. The disease may have a few family history (genetic familial myasthenia gravis). Histocompatibility antigen detected, Europe and the United States, Japan and China respectively, in patients with HLA-- DR2. HLA-B12 and DR4 related. Thymocytes functional studies have shown that the thymus myoid cell surface AChR. This receptor in the specific genetic quality impact and fetal infection, lead to thymus myoid cell type of nicotine-AChR sensitized circulating antibody produced. After systemic circulation, and in complement activation and participation, undermining postsynaptic membrane, postsynaptic membrane lead to the destruction of a series of dissolved morphological changes, which occurred symptoms of myasthenia gravis. Pathological involvement of skeletal muscle fibers small perivascular infiltration of lymphocytes, known as lymphatic overflow. Acute and severe cases, muscle fibers scattered focal necrosis, and the number of nucleation and macrophage infiltration and leakage. Some muscle fiber atrophy, muscle nuclear-intensive, was denervation changes. Advanced cases, we can see skeletal muscle atrophy, intracellular fatty change. A few patients may have focal or diffuse myocarditis like change.