Thrombophilia differences in splanchnic vein thrombosis and lower extremity deep venous thrombosis in North America

Background: The utility of thrombophilia testing in patients with splanchnic vein thrombosis (SpVT) has not previously been rigorously evaluated. The purpose of this study was to characterize differences in the prevalence of thrombophilia in patients with SpVT involving portal (PVT), mesenteric (MVT), splenic (SVT), or hepatic (HVT) veins in isolation or with multisegmental (M-SpVT) involvement compared to patients with lower extremity deep vein thrombosis (DVT). Methods: An inception cohort of patients with incident SpVT was identified for whom comprehensive thrombo-philia testing was performed between 1995 and 2005 and compared to DVT controls. Results: 341 patients with SpVT (mean age 50 ± 16 years, 53 % women) including isolated PVT (n = 112), MVT (n = 67), HVT (n = 22), SVT (n = 11), and M-SpVT (n = 129) involvement and 3621 DVT controls (mean age 55 ± 16 years, 56 % women) had comprehensive thrombophilia testing. The prevalence of abnormal results was similar for SpVT (24.6 %) and DVT (25.9 %) patients. "Strong" thrombophilias were more prevalent among SpVT patients (12.3 vs. 8.5 %, p = 0.0168). Patients with splenic (45.5 %) and mesenteric (41.8 %) thrombosis had the highest thrombophilia prevalence. Protein S deficiency was more common in SpVT patients (3.5 vs. 0.9 %, p < 0.001). In contrast, FV Leiden was more prevalent among DVT patients (15.8 vs. 10.9 %, p = 0.0497). Conclusion: The prevalence of selected thrombophilia factors differ comparing SpVT and DVT patients. The prevalence is particularly high for patients with splenic and mesenteric vein thrombosis. Whereby the finding of strong thrombophilia impacts duration of anticoagulant therapy, such testing is warranted in the evaluation of patients with unprovoked SpVT.