[Disparity between the level of activity and immunochemical determination of terminal deoxynucleotidyl transferase in leukemia].

Terminal deoxynucleotidyl Transferase (TdT) is used in diagnostic investigation and in remission surveillance of leukaemias. We have compared the results obtained by enzyme activity measurement and by immunoperoxydase technic. Discrepancies between the two assays exist in 19% of the cases; they are due in particular to the anti-TdT nature who limits its specificity, and they restrict the TdT immunochemistry determination interest.