Nicht alkoholische Steatohepatitis (NASH) – Ursachen, Diagnostik und Therapie

Kernaussagen

Definition und Pathogenese

• Die Fettleber (NAFLD, non alcoholic fatty liver disease) ist definiert als eine Ansammlung von intrahepatischem Fett, die 5 % des Gesamtgewichts der Leber übersteigt. Die NASH (nicht alkoholische Steatohepatitis) wird über das Auftreten einer zusätzlichen entzündlichen Komponente definiert.

• Fettlebererkrankungen stellen die häufigste Form einer Hepatopathie in unserer Gesellschaft dar. Als Risikofaktoren gelten Übergewicht, Hypertonus, Hyperlipidämien und der Diabetes mellitus.

• Die Erkrankung zeigt einen Progress von der reinen Fettleber über die Fettleberhepatitis (NASH) bis hin zur Zirrhose mit möglicher Karzinomentwicklung.

Diagnostik und Therapie

• Zur Diagnosestellung einer NASH wird der histologische Nachweis charakteristischer Veränderungen, der Ausschluss eines relevanten Alkoholkonsums und einer viralen Hepatitis gefordert.

• Die therapeutischen Alternativen zur Behandlung der Fettleber und assoziierter Erkrankungen sind vielfältig, führen jedoch ob der Komplexität des Krankheitsbildes zu sehr variablen und selten dauerhaften Therapieerfolgen.

• Wichtige Maßnahmen sind Gewichtsreduktion, verbunden mit einer Änderung der Lebensgewohnheiten, und ein regelmäßiges aerobes Ausdauertraining. Vielversprechende medikamentöse Therapieansätze sind derzeit Pioglitazon und Vitamin E.

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