Thrombophilic dimension of Budd chiari syndrome and portal venous thrombosis--a concise review.

Budd chiari syndrome (BCS) is characterized by venous outflow obstruction either at hepatic veins or inferior vena cava, while portal vein thrombosis (PVT) is the consequence of thrombotic occlusion in the extrahepatic venous system. The aetiology of both these disorders is complicated wherein genetic, acquired and local factors interact in the pathogenesis. Among the inherited thrombophilia, factor V Leiden mutation has shown stronger association with BCS than PVT while the converse is true for prothrombin G20210A mutation. Very few studies are available on the role of fibrinolytic potential or the single nucleotide polymorphisms (SNPs) of fibrinolysis proteins, in both BCS and PVT. Among the acquired thrombophilia, myeloproliferative disorders (MPD) are the most frequent cause, while antiphospholipid antibodies (APA) and hyperhomocysteinemia have not shown very strong association with BCS and PVT. Oral contraceptives, infection, chronic inflammatory diseases like Behcets syndrome, inflammatory bowel disease, tumors, paroxysmal nocturnal hemoglobinuria (PNH), pregnancy, puerperium, poor nutrition are some of the other acquired and local risk factors associated with both these disorders. There exists a clear geographical variation both in the clinical manifestation and the underlying aetiology. Almost all the studies have proved that a multifactorial aetiology is the requisite for the manifestation. Evaluation of an extensive thrombophilia profile is essential for optimal management of patients which is further justified with the availability of specific treatment options for at least some thrombophilia markers.