Intra-abdominal Splenosis Mimicking Metastatic Disease During Evaluation for Bacteremic Sepsis

Splenosis is an uncommon sequela of traumatic splenic rupture or splenectomy, resulting from the heterotopic autotransplantation of viable splenic tissue. These ectopic implants most commonly occur within the peritoneal cavity and often remain clinically silent for decades. On cross-sectional imaging, however, splenosis may closely resemble metastatic malignancy, lymphoproliferative disorders, or peritoneal carcinomatosis, creating diagnostic uncertainty and frequently prompting extensive oncologic evaluation. We report the case of a 60-year-old man with a remote history of traumatic splenectomy who presented with bacteremic sepsis and was incidentally found to have multiple intra-abdominal soft-tissue nodules on computed tomography. The radiographic appearance raised concern for disseminated malignancy. Blood and urine cultures grew Klebsiella aerogenes, and the patient improved with targeted antimicrobial therapy. Given the patient's surgical history and prior awareness of residual splenic implants, intra-abdominal splenosis was favored over malignancy. Mild elevations in tumor markers were interpreted as reactive changes in the setting of acute systemic infection. Definitive diagnosis was established using technetium-99m-labeled heat-damaged red blood cell scintigraphy. This case emphasizes the importance of integrating clinical history, imaging findings, and functional nuclear medicine studies when evaluating disseminated intra-abdominal lesions. Recognition of splenosis as a benign mimic of malignancy can prevent unnecessary invasive procedures and inappropriate oncologic workup, particularly in acutely ill patients.