No impact of endogenous prothrombotic conditions on the risk of central venous line‐related thrombotic events in children: results of the KIDCAT study (KIDs with Catheter Associated Thrombosis)

Abstract

Summary Background and objective Central venous lines (CVLs) are the major exogenous risk factor for deep venous thrombosis (DVT) in children. The study objective was to assess whether endogenous prothrombotic conditions contribute to the risk of CVL‐related DVT in children. Methods This was a cohort study of consecutive children with heart disease requiring CVLs for perioperative care. CVLs were inserted percutaneously in the upper venous system and patients received prophylaxis with continuous unfractionated heparin (50 u kg−1 d−1). Blood samples to test for prothrombotic conditions were collected prospectively and assayed in a blinded fashion. Outcome assessment was by screening for DVT by venography, venous ultrasound and echocardiography. Results The study population consisted of 90 children, median age 2.7 years (0 months–18 years). Prevalence rates of antithrombin deficiency, protein C deficiency, protein S deficiency, heterozygous factor V Leiden, prothrombin G20210A mutation, methylentetrahydrofolate C677TT genotype, hyperhomocysteinemia, lupus anticoagulant, anticardiolipin antibodies and increased levels of lipoprotein (a) were within the range reported for the general population. At least one prothrombotic condition was present in 38% of children and combined abnormalities in 8%. The incidence of DVT was 28% (25/90), and most DVTs were asymptomatic. None of the prothrombotic conditions showed a significant association with DVT. The population attributable risk (i.e. the risk of DVT in the overall population attributable to a specific condition) did not exceed 2.2%. Conclusion Prothrombotic conditions did not have an important impact on the risk of DVT in children with short‐term CVLs. The results of the study suggest that screening for prothrombotic conditions is not justified in this setting.

Factor VIII May Predict Catheter-Related Thrombosis in Critically Ill Children

“…Previous studies investigated the association of CVC-related DVT and inherited thrombophilias (13, 19). We found that factor VIII activity is associated with incident CVC-related DVT while G value is associated with prevalent DVT.…”

“…Their performances are likely better than those of inherited thrombophilias. Except for factor V Leiden and prothrombin G20210A mutations, which may be associated with CVC-related DVT, none of the inherited thrombophilias have been shown to increase the risk for CVC-related DVT in children (13, 19). Factor V Leiden and prothrombin G20210A mutations were not associated with DVT in our study partly because of inadequate statistical power.…”

“…We systematically tested for the most common inherited thrombophilias. We did not test for less common thrombophilias because they are not associated with CVC-related DVT (13, 19). We also did not test for D-dimer, protein C, protein S and antithrombin because they did not predict DVT in critically ill adults (14).…”

Manifestations and clinical impact of pediatric inherited thrombophilia

“…2 The presumed impact of inherited thrombophilia on the thrombotic risk of CVC-related VTE in children is challenged by results 25 In addition, in the KIDs with Catheter Associated Thrombosis study, which included 90 children with heart disease requiring CVCs in the upper venous system for perioperative care, none of the thrombophilic factors showed a significant association with CVC-related VTE. 26 VTE is one of the most serious complications in children with NS, which is attributed to a net shift in the hemostatic balance toward a hypercoagulable state by selective loss of hemostatic proteins, most notably PS and AT. 25 The reported incidence of VTE in children with NS varies between 9% and 36% based on recent literature.…”

Inherited Thrombophilia in Pediatric Venous Thromboembolic Disease: Why and Who to Test

“…Thrombophilia was found in 4% of cancer patients with VTE and in 12% of patients without VTE (21). Finally, Thom et al could not find an association between catheter-related VTE and thrombophilia in cardiac pediatric patients (23). …”