Last year my alt 23, ast 19, this year alt 34, ast 19, don't drink and rest of liver panel normal.is somthing happening or is this common variation?

How lab results work: Lab results give numbers that vary. That means if you give a tube of blood for a blood count, and a lab splits the one tube of blood into two smaller tubes, and then runs each smaller tube through the machine separately, you will get 2 different sets of lab results. The differences will be small, but 2 sets of results will not be identical. In a normal healthy person, 23 and 34 are about the same.