Evaluation Of Elevated Liver Enzymes

Abstract

There are numerous causes of elevated liver enzyme levels in both symptomatic and asymptomatic patients. As previously mentioned, ALT and AST are enzymes released from damaged hepatocytes into the blood, following hepatocellular injury or death, although they can originate from other tissues. Historical information and the physical examination are essential for the initial evaluation to determine the underlying etiology, associated systemic illnesses and to determine whether the liver injury is acute or chronic,. Aminotransferase elevations of up to five times gretar than normal may be seen in numerous chronic liver diseases as well as in acute hepatic processes. Elevations of hepatic alkaline phosphatase may be associated with cholestatic conditions. Cholestatic diseases can be categorized as to anatomic obstructions of bile flow (extrahepatic cholestasis) or as functional impairments of bile formation by the hepatocytes (intrahepatic cholestasis). Alkaline phosphatase elevations may be caused by diseases in organ systems outside the hepatobiliary system. 

Keywords

• Liver
• liver enzymes
• cholestasis

Karaciğer Enzim Yüksekliğinin Değerlendirilmesi

Öz

Semptomatik ve asemptomatik hastalarda karaciğer enzim yüksekliğinin sayısız nedenleri vardır. ALT ve AST diğer dokulardan kaynaklanabilmesine rağmen, hepatosellüler hasarı veya ölümü takiben kanda hepatosit hasarından salınan enzimlerdir. Karaciğer hasarının akut veya kronik olduğunu, altta yatan etiyolojiyi ve sistemik hastalıklarla ilişkisini anlamak için ilk değerlendirme hastanın öyküsünün alınması ve fizik muayene yapılmasıdır. Normalin beş katından daha fazla aminotransferaz yüksekliği, akut karaciğer hasarında olduğu gibi sayısız kronik karaciğer hastalığında da görülebilir. Karaciğer alkalen fosfatazın yükseklikleri kolestatik durumlarla ilişkili olabilir. Kolestatik hastalıklar hem safra akımının anatomik obstrüksiyonuna göre (ekstra hepatik kolestaz), hem de hepatosit tarafından safra formasyonunun fonksiyonel bozukluklarına göre (intra hepatik kolestaz) kategorize edilebilir. Alkalen fosfataz yükseklikleri hepatobiliyer sistem dışındaki organ sistemlerinin hastalıklarında oluşabilir. 

Anahtar Kelimeler

• Karaciğer
• karaciğer enzimleri
• kolestaz

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