Paraneoplastic leukocytosis in peritoneal dialysis

Liposarcoma (LPS) typically occurs in the extremities and retroperitoneum, but rarely occurs in visceral organs such as pancreas. Only few cases of primary pancreatic LPS have been reported in literature. Here we describe the first case of primary pancreatic LPS in a patient receiving continuous ambulatory peritoneal dialysis (CAPD). This patient was a 60-year-old female who had been on CAPD for 3 years due to kidney failure from type 2 diabetes mellitus. She presented with a 2-week history of intermittent fever measuring up to 38 degrees Celsius. The septic workup including peripheral blood, peritoneal dialysis (PD) fluid, urine, and sputum cultures were all negative. Intravenous piperacillin/tazobactam was empirically started but there was persistent fever with increasing blood leukocytosis (blood white cell count up to 37.5×10⁹/L). In addition, she developed cloudy peritoneal dialysate, suggestive of PD peritonitis, 2 weeks into the hospitalization. Piperacillin/tazobactam was then switched to intravenous meropenem and intraperitoneal vancomycin. Computerized tomography scan of the abdomen showed a large heterogeneous enhancing mass with central hypoattenuating area arising from the pancreatic tail. There were also local invasion and multiple metastatic lesions. Ultrasound-guided fine-needle biopsy of the abdominal mass confirmed the diagnosis of primary dedifferentiated LPS of the pancreas. In view of the advanced nature of the disease, she was treated with palliative chemotherapy. Her clinical condition deteriorated progressively and she passed away from pneumonia 10 months after the diagnosis of LPS. Our case shows that patients on CAPD with pancreatic LPS can develop symptoms mimicking infectious peritonitis and also highlights the importance of considering malignancies in the differential diagnosis of fever and unexplained leukocytosis after ruling out infective causes.