gamma-Glutamyltransferase and alkaline phosphatase activities compared in serum of normal children and children with liver disease.

We compared alkaline phosphatase (EC 3.1.3.1) and gamma-glutamyltransferase (EC 2.3.2.2) activities in sera from children with various hepatic diseases with values for normal children. Although values for both enzymes are above normal in essentially the same liver disorders, the latter is much more specific and sensitive. A single value for alkaline phosphatase, measured at any time during childhood or at any stage of liver disease, is extremely difficult to interpret. We suggest that measurement of gamma-glutamyltransferase routinely replace alkaline phosphatase as a screening test and in following patients with obstructive or infiltrative hepatic disorders. We give reliable reference intervals for gamma-glutamyltransferase covering the entire pediatric age group.