2581 Acute Lymphoblastic Leukemia Presenting With Mesenteric Ischemia

Abstract

INTRODUCTION: Acute lymphoblastic leukemia (ALL) is a malignancy of B/T-cell lymphoid precursors that predominantly affects the pediatric population. Presenting symptoms are usually related to bone marrow and organ infiltration. Arterial thrombosis is extremely rare and seldom seen as a presenting manifestation of acute leukemia. To our knowledge, we present the first case of mesenteric ischemia due to complete occlusion of the superior mesenteric artery (SMA) as the first manifestation of T-cell ALL. CASE DESCRIPTION/METHODS: A 44-year-old male presented with severe upper abdominal pain, vomiting and diarrhea for 1 day. Physical examination was notable for diffuse abdominal tenderness and pain out of proportion to exam. Initial laboratory data showed WBC of 2.02 × 103/mL with 30% blasts. Lactic acid was within normal limits. CT of the abdomen revealed a thrombus in the SMA resulting in complete occlusion (Figure 1). An emergent open SMA thrombectomy was performed following failure of catheter-directed thrombolysis. Diffuse ischemic changes were visualized in the jejunum necessitating a partial small bowel resection (Figure 2). Intraoperative transesophageal echocardiogram was negative for intracardiac thrombus or valvular pathology. A peripheral blood smear revealed a large population of immature cells with fine chromatin and a high nuclear to cytoplasmic ratio (Figure 3). Flow cytometry showed a large population of blasts constituting about 22% of cells, positive for CD5, CD7, and CD10. The immunophenotypic appearance confirmed the diagnosis of T-ALL. He was referred to medical oncology for bone marrow biopsy. DISCUSSION: This is the first reported case of acute arterial occlusion in the SMA leading to mesenteric ischemia as the initial manifestation of T-cell ALL. SMA thromboembolism typically occurs in the setting of atherosclerosis or cardiac pathology, which were absent in this case. Venous thromboembolism is a well-documented complication of acute leukemia that negatively impacts mortality. The inhibition of anticoagulant proteins, production of prothrombotic factors, alteration of the vascular endothelium, and increased vascular adhesion of leukemic cells are all potential contributors. However, arterial occlusion is extremely unusual and almost exclusively seen in acute promyelocytic leukemia (APL). This report illustrates that an unexplained arterial or venous thrombotic event in a previously healthy patient could be a sign of an underlying malignancy.