[DoubleRR]

ALT is short for alanine transferase. This is an enzyme that is present in the cells in the liver. In order for it to be found in elevated quantities in the blood stream, liver cells have to be leaking the enzyme. So rises in this enzyme indicate damage to liver cells sufficient to cause them to leak the enzyme. Rises in ALT, even large rises, can occur due to problems that don't cause much change in liver function, though.
Trauma, liver toxins, blood clots and other insults to the liver which damage a large number of cells in a small area of the liver may produce high rises in ALT that are essentially meaningless, as the liver will recover with no problem.

On the other hand, chronic liver diseases that constantly produce damage to the liver but do so slowly may never cause strong rises in the ALT levels even though liver function is deteriorating significantly.

oops you said AST.
Aspartate aminotransferase (AST) is also an enzyme found in the liver, red blood cells (RBCs) and in muscle tissue; damage to any of these can result in increased levels of AST in the blood. An elevation in AST signifies more severe damage to the cells than an elevation in ALT. I still am not sure that there is anything to worry about , but you may want to wait and see if the levels "level out" before you send her in for an operation.