[The medical laboratory issues about recommendation on uniform cutoff values of "Normal" ALT in the ACG guidelines].

In the recent clinical guidelines dealing with laboratory tests for liver disease evaluation, the American College of Gastroenterology (ACG) recommends ALT upper reference limits of 33 U/L for males and 25 U/L for females, and individuals with results above these "normal" cutoffs should be further investigated. Considering the differences between laboratory assays measuring ALT in our country, the uniform ACG "normal" range may not be suitable for Chinese population. On the other hand, reference upper/lower limits should not be equated with clinical decision thresholds. Simply acting in accordance with the reference range from ACG guidelines for ALT may lead to overdiagnosis and unnecessary follow-up examinations.