Abstract: PUB301
A Case of Retroperitoneal Fibrosis in Chronic Myelomonocytic Leukemia: Coincidence or Association?
Session Information
Category: Onconephrology
- 1700 Onconephrology
Authors
- Alvarado, Analicia Marie, Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina, United States
- Kshatri, Michael Ranjan, Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina, United States
- Woldemichael, Jobira A., Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina, United States
Introduction
Retroperitoneal fibrosis (RPF) is a rare fibroinflammatory disorder characterized by the proliferation of fibrous tissue in the retroperitoneal space. While typically idiopathic, RPF can also be secondary to malignancies, infections, autoimmune diseases, or certain medications. Acute kidney injury in chronic myelomonocytic leukemia (CMML) can be a result of several mechanisms, including prerenal, glomerular injury, tubulointerstitial involvement, lysozyme-induced nephropathy, and leukemic infiltration. Given CMML’s potential for systemic effects and immune dysregulation, atypical fibrotic manifestations like RPF could occur.
Case Description
A 71-year-old male presented with generalized malaise and abdominal pain. Initial labs revealed acute kidney injury with a creatinine of 2.1 mg/dL (baseline 1.4 mg/dL). MRI of abdomen revealed bilateral perinephric stranding, periureteral thickening, and perivascular involvement along with bilateral hydronephrosis (Figure1).
Due to concern for obstructive uropathy, bilateral ureteral stents were placed. Despite intervention, renal function worsened necessitating hemodialysis temporarily. Extensive workups for secondary causes of RPF were negative. IgG4 levels were normal. Renal biopsy demonstrated diffuse acute tubular necrosis with isometric vacuolization and mild interstitial fibrosis.
The peripheral smear showed persistent monocytosis, prompting hematologic evaluation. Bone marrow biopsy confirmed CMML. The patient’s renal function gradually improved while on corticosteroids for presumed RPF.
Discussion
This case highlights a rare presentation of RPF in a patient with newly diagnosed CMML. The differentiation between idiopathic and secondary RPF remains challenging. In the absence of frequently reported direct association or histopathologic evidence linking CMML to RPF, the case may represent a coincidental occurrence. However, Clinicians should maintain a high index of suspicion for atypical presentations of acute kidney injury in hematologic malignancies like CMML.