Clinical importance of prothrombotic risk factors in pediatric patients with malignancy -: impact of central venous lines

To evaluate the role of inherited thrombophilia in the development of central venous line (CVL)-related thrombosis, the following parameters were determined in 77 pediatric-oncologic patients with CVL: activated protein C (APC)-ratio, factor V (FV) G1691A and prothrombin G20210A mutation, protein C, protein S, antithrombin, coagulation factor XII, lipoprotein (a) and homocysteine. An inherited prothrombotic risk factor was found in 17 patients (23%). Four out of 14 patients with a single defect (hyperlipoproteinemia, heterozygous FV G1691A and pro thrombin G20210A mutation, protein C deficiency type I) and all three patients with combined defects (heterozygous FV G1691A mutation combined with heterozygous prothrombin G20210A variant, protein S deficiency or hyperlipoproteinemia) suffered from CVL-related thrombosis. In 11 out of 77 patients (14%) a CVL-related thrombosis was detected. In 2 children thrombosis occurred a few days after asparaginase therapy and in another three thrombosis was associated with CVL-related septicemia caused by Staphylococcus epidermidis. After removal of CVL, thrombosis was detected in 5 children, in 2 without clinical symptoms but in the presence of inherited prothrombotic risk factors. Conclusion The present study demonstrates the clinical importance of CVL in combination with inherited thrombophilia in the development of thrombosis in pediatric-oncologic patients. Before or shortly after insertion of CVL, patients should be tested for the presence of factor V G1691A mutation, prothrombin G20210A variant and increased lipoprotein (a) values.