Thrombosis of the splenoportal axis after splenectomy

Background and aims Thrombosis of the portal system is a potentially life-threatening complication after splenectomy. The reported incidence is low (congruent to 1%), however may be underestimated due to difficult in making the diagnosis. The factors associated with its development and the clinical outcome are poorly characterized. The aim of this study was to assess the incidence, risk factors, treatment, and outcome in series of consecutive cases. Materials and methods All patients who had undergone a splenectomy (both open and laparoscopic) between January 1997 and December 2004 at the Department of Surgery of University of Milan Bicocca were retrospectively reviewed. Twelve cases of thrombosis (7.6%) among 158 splenectomies were identified. No significant differences were noted in age, gender, and surgical approach between patients who developed thrombosis and those who did not. Indication for splenectomy in patients with thrombosis were myeloproliferative disorders (n=5), hemolytic disease (n=4), and lymphoproliferative disorder (n=3). All patients had splenomegaly (mean 1.380 kg, range 0.400-3.120 kg). Results Among patients with myeloproliferative disorders, five (33%) developed the complication, compared with 4 of 35 (11.5%) with hemolytic disease. Patients with both splenic weight > 2.500 kg and myeloproliferative disorders had 80% incidence of portal thrombosis. Preoperative prophylactic anticoagulant therapy with low molecular weight heparin was administered in each case. All these patients had fever, abdominal pain, or leukocytosis. All diagnoses were made by contrast-enhanced computed tomography (CT) scan and ecocolordoppler ultrasonography, and anticoagulation therapy was initiated immediately. Treatment within 15 days after splenectomy was successful in all patients, while delayed treatment was ineffective. Conclusions Portal thrombosis should be suspected in patients with fever or abdominal pain after splenectomy. Patients with myeloproliferative disorders and hemolitic diseases are at higher risk, as well as patients with marked splenomegaly. A high index of suspicion, early diagnosis, and prompt anticoagulation therapy are the keys to a successful outcome.