Retroperitoneal fibrosis-the long and winding path

Area of Science:

• Nephrology
• Rheumatology
• Radiology

Background:

• Retroperitoneal fibrosis (RPF) is a rare systemic disease, often idiopathic and potentially autoimmune-related (IgG-4).
• Diagnosis is challenging due to non-specific symptoms like back pain, elevated ESR, and renal impairment, often requiring exclusion.

Observation:

• A 57-year-old female presented with back pain, anemia, elevated ESR, and declining renal function.
• Initial investigations focused on bone metastases and pelviureteric junction dysfunction, delaying a CT scan and RPF diagnosis.
• The patient acutely developed hyperkalemia and Acute Kidney Injury (AKI) stage 3, prompting further investigation.

Findings:

• CT and MRI revealed bilateral hydronephrosis and a retroperitoneal mass compressing the ureters, consistent with RPF.
• Ureteral obstruction was caused by ureters embedding into dense retroperitoneal fibrous tissue.
• Laparoscopic retroperitoneal biopsy confirmed RPF; steroid therapy and ureteral stenting led to satisfactory outcomes.

Implications:

• This case underscores the importance of considering RPF in patients with unexplained renal impairment and back pain.
• Highlights potential diagnostic delays due to cognitive biases and atypical investigation pathways.
• Emphasizes the critical role of timely cross-sectional imaging (CT/MRI) and biopsy for accurate RPF diagnosis and management.