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Retroperitoneal fibrosis (RPF) is a rare disease characterized by the presence of fibro-inflammatory tissue around the aorta entrapping the adjacent structures. RPF can be idiopathic or secondary to many disorders. The physiopathology is unknown but can be part of the spectrum of IgG4 related diseases. Imaging studies and inflammatory markers are essential for initial evaluation and follow-up. Biopsy is usually not recommended. The first line of treatment is corticosteroids associated or not with immunosuppressive drugs. In case of ureteral obstruction with renal failure, ureteral stent placement or nephrostomies are recommended. Initial response to treatment is usually good but relapses are frequent.