I don't think I'd be too worried about that spike in AST. There are so many things that can cause AST to elevate. Something as simple as taking a tylenol or exercising vigorously, can do it. A single value is really not meaningful. A trend over time is what you want to watch.
Why are you testing so frequently? Do you have hep c? Do you have liver damage? Are you seeing a doctor? What does your doctor say?
High values
High levels of AST may be caused by:
Liver damage from conditions such as hepatitis or cirrhosis.
Decay of a large tumor (necrosis).
A heart attack or heart failure.
Many medicines, such as statins, antibiotics, chemotherapy, aspirin, narcotics, and barbiturates.
Having taken high doses of vitamin A.
Kidney or lung damage.
Mononucleosis.
Some types of cancer.
Good luck