Superior Mesenteric Artery Thrombosis as a Complication of Polycythemia Vera: A Case Report

Background and Clinical Significance: Polycythemia vera (PV) is a myeloproliferative neoplasm associated with a markedly increased risk of arterial and venous thrombosis. Superior mesenteric artery (SMA) thrombosis is an exceptionally rare but potentially fatal complication. Case Presentation: We report the case of a 25-year-old man with previously diagnosed, JAK2-negative PV who presented with acute abdominal pain, nausea, vomiting, abdominal distension, and absence of stool and flatus, consistent with clinical features of intestinal obstruction. Laboratory testing revealed marked leukocytosis, elevated inflammatory markers, and subtherapeutic anticoagulation (INR 1.2) despite ongoing oral therapy. Multislice computed tomography demonstrated occlusion of the SMA with developed collateral circulation and features of small-bowel ischemia. Due to progression to an acute abdomen, emergency laparotomy was performed, revealing jejunal perforation with preserved viability of the remaining bowel. Primary closure was carried out, followed by peritoneal lavage and drainage. The postoperative course was uneventful. After correction of anticoagulation and therapeutic INR monitoring, no recurrent thrombotic events were observed during follow-up. Conclusions: This case underscores the importance of strict anticoagulation control, early imaging, and prompt surgical intervention in patients with PV, even in young individuals and in atypical vascular territories.