ALT levels in your blood are usually low, but they can rise if you have liver disease, damage, or toxicity. ALT blood tests are often part of standard blood test panels.

Kariv et al. reviewed the ALT test results of 17,496 patients from an Israeli health organization's database, in order to assess the true upper normal limit of serum ALT.

Strategy F: test all patients from prevalent countries as well as those with an ALT exceeding twice the upper-limit of normal.