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Alcoholic hepatitis is characterized by an AST:ALT > 2. It is thought that this transaminase imbalance occurs
in alcoholics secondary to a hepatic deficiency of pyridoxal-6-phosphate (a cofactor for ALT enzymatic
activity).
can any1 explain it better?:rolleyes:
 

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can any1 explain it better?:rolleyes:
I am not sure what you are asking, but this is what I understood about a higher AST in alcoholic hepatitis from Pathoma.

The reason for a higher AST is because it is a mitochondrial enzyme. Alcohol is a mitochondrial poison which will therefore affect the AST more than ALT.

I hope that is answering the question
 

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Go through(chapter 1) Goljan 3rd edition>>>>> It says ALT which is a cytoplasmic enzyme as therefore more specific for Liver cell necrosis than AST and on the contrary AST which is a mitochondrial enzyme preferentially elevated more in alcoholic hepatitis than ALT as because Alcohol damages mitochondrial membrane.Mitochondria are intimately involved in the generation of and defense against reactive oxygen species (ROS). Mitochondria are themselves targets of oxidative stress and also contribute to mechanisms by which oxidative stress-related signals control cell fate. Ethanol promotes oxidative stress, both by increasing ROS formation and by decreasing cellular defense mechanisms.
 

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why AST> ALT in alcoholic hepatitis

hey got this frm harrissons internal medicine:

1. ALT is exclusive for liver where as AST is found in other organs like heart, skeletal muscle, brain, kidney et, so ALT more specific than AST

2. In alc.hepatitis, levels of AST: ~300, where as ALT: often normal(reason for this given below)
i.e, AST/ALT ratio= > 2:1 ( a ratio of 3:1 is confirmative)& the reason for low ALT is d/t alcohol induced deficiency of pyridoxal phosphate

hope that clears Happy-2
 

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hey got this frm harrissons internal medicine:

1. ALT is exclusive for liver where as AST is found in other organs like heart, skeletal muscle, brain, kidney et, so ALT more specific than AST

2. In alc.hepatitis, levels of AST: ~300, where as ALT: often normal(reason for this given below)
i.e, AST/ALT ratio= > 2:1 ( a ratio of 3:1 is confirmative)& the reason for low ALT is d/t alcohol induced deficiency of pyridoxal phosphate

hope that clears Happy-2
But pyridoxal phosphate is also a cofactor for AST right ? bcoz vit B6 is a cofactor for all transamination reactions , then why only ALT level is low , can you plz clarify that?

Thanks..
 
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