Guenther G, Núñez-Orozco L

Language: Spanish
References: 22
Page: 340-345
PDF size: 179.38 Kb.

ABSTRACT

Introduction: Myasthenia gravis (MG) is an autoimmune disorder with a variable response to treatment. Refractory cases may pose a significant challenge in clinical practice. Objectives: To describe the prevalence of refractory MG in a third-level reference hospital in Mexico and to evaluate the clinical response to rituximab in selected refractory cases. Methods: We consulted clinical files of patients diagnosed with MG in the Department of Neurology of the National Medical Center “20 de Noviembre”, ISSSTE, from January 2000 to December 2010, and identified refractory cases who received rituximab, 1 g IV per week, during 2 weeks of every 6 months in a year (total cumulative dose: 4 g). Muscle strength was evaluated by means of the Quantitative Myasthenia Gravis Score (QMGS: 0 the best and 39 the worst scoring) at 3, 6 and 9 months postreatment. Results: A total of 376 MG cases were registered in a 10-year period. Six (1.6%) patients were refractory to conventional treatment and 4 of them (two women and 2 men) received rituximab. All patients presented significant improvement in muscle strength: one patient showed a 75% reduction in QMGS between basal and 9-month evaluations, other patient showed 20% reduction, other 59% and the last one 19%. No major adverse reactions were registered during followup. Conclusion: Treatment with monoclonal anti-CD20 antibodies in refractory MG represents a therapeutic option that shows favorable results.

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