INCREASED THROMBIN GENERATION DURING FIBRINOGEN AND PLATELET RECOVERYAS AN EXPLANATION FOR HYPERCOAGULABILITY IN CHILDREN WITH L-ASPARAGINASE THERAPY FOR ALL OR NHL - A PRELIMINARY-REPORT

Three out of 21 patients treated at the Children's Hospital of Eastern Switzerland for ALL or NHL with the respective BFM-90 protocols exper ienced thrombotic complications during Erwinia L-asparaginase therapy. We therefore investigated the development of the haemostatic imbalanc e in six children during the induction phase of both protocols. In the average, elevated thrombin generation was found simultaneously to an increase in fibrinogen, cross-linked fibrin degradation products and p latelet counts between protocol days 28 to 35. This period thus seems to harbour an increased potential of hypercoagulability which could ex plain the accumulation of thrombotic complications described by Sutor et al. [5]. Moreover, day to day investigations just before and one da y after L-asparaginase administration did not show any relevant change in the above named parameters, thus rather indicating a cumulative th an a single dose effect of Erwinia L-asparaginase therapy on the coagu lation system. These findings lead to the question if the prophylactic use of anticoagulants might reduce the hypercoagulability seen during L-asparaginase therapy, which is currently under investigation in our institutions.