Myasthenia gravis: aktuelle Antikörperdiagnostik und Aspekte zum therapierefraktären Verlauf

Zusammenfassung

Die erworbene Myasthenia gravis (MG) wird durch Antikörper gegen verschiedene Bestandteile der neuromuskulären Endplatte verursacht. In den meisten Fällen wird die typische belastungsabhängige Muskelschwäche durch Antikörper gegen den Acetylcholinrezeptor (AChR) verursacht, bei einem geringeren Anteil der Patienten finden sich seltenere Antikörper gegen Muskel-spezifische Kinase (MuSK) oder verwandte Proteine wie Agrin, Cortactin oder Low-Density-Lipoproteinrezeptor-verwandtes Protein 4 (LRP4). Durch fachgerechte und konsequente Behandlung kann in der überwiegenden Mehrheit der Patienten mit Acetylcholin-Rezeptor-Antikörper (AChR-AK) positiver Myasthenie eine nahezu Vollremission mit normaler Lebenserwartung und guter Lebensqualität erreicht werden. Etwa 10 bis 15 % der Patienten sprechen nicht adäquat auf aktuell empfohlene Therapien an und bilden die Gruppe der refraktären MG. Der Artikel gibt einen Überblick über die derzeitige Antikörperdiagnostik und Aspekte zum therapierefraktären Verlauf.

Abstract

Acquired myasthenia gravis (MG) is an autoimmune disease that leads to fluctuating muscle weakness and fatigue, caused by circulating antibodies against different structures of the neuromuscular junction. In most patients, antibodies against acetylcholine receptor (AChR) can be detected. In a smaller proportion of patients with and without AChR antibodies, antibodies to muscle-specific kinase (MuSK), or related proteins such as agrin, cortactin and low-density lipoprotein receptor-related protein 4 (LRP4), are present. With current therapy, most patients achieve a stable condition with good quality of life and normal life expectancy. Nevertheless, 10 to 15 % of patients fail to respond ad equately to current therapies and are defined as refractory myasthenia gravis. Their clinical course is characterized by recurrent episodes of severe, acute deterioration, which sometimes appear life threatening. This article gives an overview of the current state of myasthenic antibody diagnostics and recommended treatment of refractory myasthenia gravis.

Schlüsselwörter

Myasthenia gravis - Refraktär - Immunsupression - Eculizumab

Key words

Eculizumab - Myasthenia gravis - Refractory - Immunosuppression

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