Objective：To study the etiological factors and the treatment methods of portal vein thrombosis (PVT) and mesenteric venous thrombosis (MVT) after splenectomy.
Methods：Clinical materials of 12 patients with PVT and MVT after splenectomy  were analyzed retrospectively.
Results：Venous thrombosis occurred in 12 of 280 post-splenectomy patients (4.3%) including nine patients with PVT（4.3%）and three patients  with MVT(1.1%). All of the PVT patients had leukocytosis, increase  platelet count,  positive  D-dimer and abnormal  thromboplastic function. PVT and MVT were discovered with color ultrasonography, CT, and MRI in nine patients, with superior mesenteric artery angiography in one case, and at exploratory laparotomy because of acute intestinal obstruction in two cases. Nine patients were cured by anti-coagulation and thrombolytic therapy. Two MVT cases had small intestinal necrosis underwent intestioal resection and anastomosis, postoperative systemic anticoagulation and thrombolytic therapy, and were cured. One case of acute PVT thrombosis with progression to intrahepatic portal vein, died of liver failure.
Conclusions：Post-splenectomy portal system thrombosis is related with many factors. Early diagnosis and prompt anticoagulant therapy has an important impact on prognosis. If results of non-operative therapy are not satisfactory, prompt surgical therapy is advocated.