Objective: To determine the association between catheter-related thromboses and hereditary causes of thrombophilia, including the factor V Leiden mutation, deficiencies of protein C or protein S, or increased lipoprotein (a).
Study design: To evaluate the incidence of genetic risk factors for familial thrombophilia in catheter-related thrombosis, 163 consecutively admitted infants and children (cardiac disease and catheter placement [C] n = 140; Broviac catheter [B] n = 23) were prospectively investigated. In addition, an age-matched, healthy control group undergoing elective surgery (S: n = 155) was investigated.
Results: Heterozygous factor V Leiden mutation was diagnosed in 20 of the 318 study subjects (C: n = 5; B: n = 4; S: n = 11), homozygous factor V Leiden mutation was found in two subjects (C: n = 1; S: n = 1), protein C deficiency type I was diagnosed in nine subjects (C: n = 4; B: n = 1; S: n = 4), and five subjects showed increased lipoprotein (a) (C: n = 3; S: n = 2). The frequency of thrombosis (C: n = 13; B: n = 5) in patients with familial thrombophilia was significantly higher (p < 0.0001; chi square: 27.79) in the catheter groups (15 of 17 subjects) than in control subjects after minor elective surgery (none of 18). Fifteen of the 18 infants with thrombosis had congenital thrombophilia; two children with congenital thrombophilia did not have documented thrombosis, and three infants with vascular occlusion had no inherited predisposition to thrombophilia.
Conclusions: Genetic risk factors for familial thrombophilia play an important role in the manifestation of catheter-related thromboembolism in children.