Treatment of Myasthenia Gravis
- 2.6k Downloads
Myasthenia gravis (MG) is an antibody-mediated, neuromuscular transmission disorder, which ranges in clinical manifestations of ocular myasthenia that may be visually disabling to myasthenic crisis with patients suffering life-threatening respiratory insufficiency. MG also has pathophysiologic subgroups based on presence or absence of acetylcholine receptor or muscle-specific kinase antibodies and presence of thymoma. Cholinesterase inhibitors partially improve weakness, but the vast majority of patients require therapies that moderate the autoimmune attack. Mortality of MG has been reduced over the last century, but adverse effects of treatment compromise patient care and rigorous evidence to guide the clinician are lacking.
KeywordsMyasthenia gravis Ocular myasthenia Acetylcholine receptor Corticosteroid Azathioprine Mycophenolate mofetil Cyclosporine Intravenous immunoglobulin Plasma exchange Complement Acetylcholine receptor antibody Thymectomy Muscle specific kinase
H.J. Kaminski receives support from grants from the National Institutes of Health R01 EY14837 and R01 NS42685.
Conflicts of interest: V. Kumar: none; H.J. Kaminski has performed consultations for GlaxoSmithKline, Bayhill Therapeutics, Cytokinetics, and Varleigh Limited.
Papers of particular interest, published recently, have been highlighted as: • Of importance
- 2.• Leite MI, Jacob S, Viegas S, et al.: IgG1 antibodies to acetylcholine receptors in ‘seronegative’ myasthenia gravis. Brain 2008, 131:1940–1952. This article indicates that even patients who do not have antibodies directed against the AChR or MuSK likely have low levels of serum antibodies that bind the AChR. Some of these seronegative patients still may have antibodies directed at other proteins.CrossRefPubMedGoogle Scholar
- 6.A randomised clinical trial comparing prednisone and azathioprine in myasthenia gravis. Results of the second interim analysis. Myasthenia Gravis Clinical Study Group [no authors listed]. J Neurol Neurosurg Psychiatry 1993, 56:1157–1163.Google Scholar
- 15.• Sanders DB, Hart IK, Mantegazza R, et al.: An international, phase III, randomized trial of mycophenolate mofetil in myasthenia gravis. Neurology 2008, 71:400–406. This study was a well-performed, randomized, placebo-controlled trial that showed no benefit of mycophenolate and prednisone compared with prednisone alone. The study likely did not have long enough periods of study.CrossRefPubMedGoogle Scholar
- 16.• Muscle Study Group: A trial of mycophenolate mofetil with prednisone as initial immunotherapy in myasthenia gravis. Neurology 2008, 71:394–399. This study was a well-performed, randomized, placebo-controlled trial that showed no benefit of mycophenolate and prednisone compared with prednisone alone. The study likely did not have long enough periods of study.CrossRefGoogle Scholar
- 18.Ponseti JM, Gamez J, Azem J, et al.: Post-thymectomy combined treatment of prednisone and tacrolimus versus prednisone alone for consolidation of complete stable remission in patients with myasthenia gravis: a non-randomized, non-controlled study. Curr Med Res Opin 2007, 23:1269–1278.CrossRefPubMedGoogle Scholar
- 34.Gajdos P, Chevret S, Toyka K: Plasma exchange for myasthenia gravis. Cochrane Database Syst Rev 2002, (4):CD002275.Google Scholar
- 36.• Newsom-Davis J, Cutter G, Wolfe GI, et al.: Status of the thymectomy trial for nonthymomatous myasthenia gravis patients receiving prednisone. Ann N Y Acad Sci 2008, 1132:344–347. The article describes the first randomized, single-blinded, controlled trial of thymectomy for patients with MG. The study is about two-thirds completed at the time of publication of this review.CrossRefPubMedGoogle Scholar