Retroperitoneal lymphadenopathy: An underappreciated contributor to acute kidney failure in patients with cancer

Abstract

Introduction: Retroperitoneal lymphadenopathy represents a unique and infrequent complication within various malignancies. This case report exemplifies the intricate diagnostic challenges that arise when identifying nondilated obstructive nephropathy in the context of retroperitoneal lymphadenopathy due to diffuse large B-cell lymphoma (DLBCL), particularly when conventional imaging fails to reveal the hallmark feature of hydronephrosis. Case description: We present a 66-year-old male with relapsed chronic lymphocytic leukemia post-allogeneic stem cell transplantation. His direct admission to the hematology/oncology service was due to failure to thrive. Despite the absence of hydronephrosis on imaging, the patient developed volume overload and increased serum creatinine levels. An ultrasound unveiled mild bilateral collecting system dilation, while laboratory findings did not provide valuable insight into the underlying etiology. A Lasix renal scan confirmed split renal function with minimal bilateral excretion. High clinical suspicion resulted in an MRI scan showing interval enlargement of retroperitoneal lymph nodes and pelvicaliectasis, which prompted urological and interventional radiology involvement. Conclusions: This case underscores the complexity of diagnosing retroperitoneal lymphadenopathy and pelvicaliectasis, in DLBCL, particularly when hydronephrosis is absent on imaging. It emphasizes the significance of clinical acumen, collaboration among specialties, and the use of advanced imaging techniques. Timely recognition of nondilated obstructive nephropathy in the setting of retroperitoneal lymphadenopathy is pivotal for guiding appropriate management strategies and optimizing patient outcomes in the intricate clinical setting.