Alt

ALT refers to an enzyme that catalyzes a reversible transamination between L- alanine and 2- oxoglutarate to pyruvate and L- glutamate (Gressner 2012).

ALT, together with the enzyme AST (GOT), is also referred to as "transaminases" (Kindermann 2007).

ALT, together with AST (GOT) and GLDH (glutamate dehydrogenase), are indicators of liver cell damage (Herold 2022).

ALT itself represents a liver-specific enzyme (Herold 2022). It is localized 85% in the cytosol and 15% in the mitochondria of the liver cell (Halwachs- Baumann 2011).

The ALT- normal value is < 35 U / l in women and < 45 U / l in men (Lohmann 2020).

An increase in ALT is a clear indication of liver or biliary disease (Lohmann 2020).

Otherwise, it can be caused by:

- physical stress

In this case, there is only a slight increase in ALT - in contrast to AST, which can rise sharply due to physical activity (Kindermann 2007).

- acute hepatitis

- biliary tract diseases

- (toxic) liver damage (Lohmann 2020)

- Steatohepatitis (Halwachs- Baumann 2011).

Regarding the cause of steatohepatitis, the quotient AST / ALT (GOT / GPT) plays a role: if this is < 1, it is an indication of a non-alcoholic cause; if, on the other hand, it is ≥ 2, it indicates an alcohol-related steatohepatitis (Halwachs- Baumann 2011).

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3. Herold G et al (2022) Internal medicine. Herold Publishers 516
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5. Kindermann W, Dickhuth H H, Nieß A, Röcker K, Urhausen A (2007) Sports cardiology: physical activity in heart disease. Steinkopff Verlag Darmstatdt 121
6. Lohmann M (2020) Understanding laboratory values: blood, urine and stool analyses, normal values at a glance, technical terms and important abbreviations. Mankau- Verlag Murnau Chapter: Physical disorders and organ diseases.