Hello, taffis,
Elevated liver enzymes could be caused by a number of factors.
Hepatitis viruses and other viral diseses such as mononucleosis
can cause this. Certain genetic enzyme deficiency can do this.
In western culture, alcohol is number one cause. Next is
gallbladder and bile duct issues, pancreas problems can cause
liver test abnormalities. Most importantly, drugs both over the
counter and prescription drugs can elevate liver enzymes.
Auto-immune diseases such as lupus,
rheumatoid arthritis can
affect liver and kidneys.
I am glad that your MRI tests, endoscopy and other blood
work were all normal.
As for Flu shot causing elevated liver enzymes , clinically we
don't see it unless as part of severe
allergic reaction to the shot.
Influenza virus itself can cause elevated liver enzymes during
active infection.
Hope this gives you some idea of where to look.
I wish you well.