causes of elevated liver enzymes

About 10 or 12 years ago I donated blood.  I later received a letter from the blood banking saying that I had "elevated liver enzymes."  I do not remember the specifics. but I assume they were implying that I had been exposed to hepatitis.  I did not have it checked out by a doctor at the time, but I have had no problems since and am in good overall health.  

I see two possibilities that could have contributed to the test results.  I was in college at the time and, though I did not drink often or habitually, I had gotten very drunk a day or two before the blood draw.  I had also undergone a three-injection hep B vaccination earlier that year.  Could either of these have contributed and, if so, will I still be allowed to donate blood?  Or is such a test result an immediate ban on future donations?  I feel very strongly about the blood donation program and would like to start donating again so any information would be hugely appreciated.