What might cause elevated liver alt ast levels?

Many conditions: Including Hepatitis of all forms, drug adverse effects, liver diseases , GB diseases, CHF, ETOH and etc

Liver.: The presumption would be that this is an issue with the liver or biliary system. However, could also be something quite simple, such as a medication you had taken or even a food that you ate. It’s always helpful to repeat the levels, along with a full liver function panel including GGT and LDH. If these numbers are still high, then more fancy blood testing and an abdominal ultrasound follows.