**Abstract**

Beta (β)-thalassemia major, a chronic inherited hematological disease, leads to chronic anemia in affected children. One of the options for treatment is splenectomy. However, this treatment involves risk of many complications, one of which is portal vein thrombosis (PVT). The risk factors include exposure of phosphatidyl-serine of abnormal red blood cells (RBCs), increased activation, aggregation and a number of platelets and nucleated RBCs after splenectomy, increased endothelial activation, decreased nitric oxide, organ dysfunction, and thrombophilia. PVT is either complete or partial obstruction and has fatal complications, especially after splenectomy and late diagnosis without effective treatment. Diagnosis is typically made with X-ray. Generally, the incidence of PVT is between 1.7% and 9.2%. Initially, it is asymptomatic; symptoms appear gradually as thrombosis progresses. The easiest way to differentiate it from other conditions is via imaging study like Doppler ultrasound. It is usually associated with prolonged prothrombin time (PT). D-dimer and alkaline phosphatase are generally high. The treatment is the same for both the acute and chronic forms and includes the treatment of causal factors, prevention of thrombus extension, and achievement of patency of the portal vein via regular RBC transfusion and antithrombotic agents.

**Keywords:** β-thalassemia, portal vein thrombosis (PVT), splenectomy, thrombocytosis, doppler ultrasound, anticoagulant, transfusion
