Infected splenic artery pseudoaneurysm within a complex splenic cystic lesion: CT angiography pitfalls and surgical correlation.

Complex cystic splenic lesions can pose considerable diagnostic difficulty because infectious, hemorrhagic, and neoplastic processes frequently show overlapping imaging features, and splenic artery pseudoaneurysm is a rare but potentially fatal vascular complication requiring prompt recognition. We report the case of an 85-year-old male who presented with a persistent systemic inflammatory syndrome; contrast-enhanced multiphasic CT and CT angiography with 3D reconstruction demonstrated a large complex cystic splenic lesion harboring a splenic artery pseudoaneurysm, and, given the high risk of rupture, the patient underwent splenectomy with vascular control, with surgical and histopathological findings confirming an infected splenic cystic lesion complicated by splenic artery pseudoaneurysm without evidence of malignancy and microbiological culture of the infected collection yielding Lancefieldella rimae. This case illustrates the value of arterial-phase CT and CT angiography in differentiating pseudoaneurysmal enhancement from hemorrhagic or inflammatory cystic splenic lesions, and underscores that early recognition is critical to guide surgical planning and to prevent catastrophic hemorrhagic rupture.