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Retroperitoneal fibrosis
Retroperitoneal fibrosis is inflammatory-fibrotic tissue that wraps the lower aorta and iliac arteries and entraps the ureters; it causes bilateral hydronephrosis and kidney failure, and is treated by relieving obstruction (stents or nephrostomy) and steroids, after a malignant cause has been excluded.
Why it matters in the exam
The exam shows a man in his fifties or sixties with dull back or flank pain, fatigue, a high ESR and CRP, and kidney failure with bilateral hydronephrosis. Imaging shows a cuff of tissue around the aorta below the renal arteries and the middle ureters drawn inward (medial deviation). About 70 percent of cases are idiopathic, and some belong to IgG4-related disease. Secondary causes: drugs (methysergide and ergot derivatives, and sometimes beta-blockers and hydralazine), malignancy (lymphoma, metastases), radiotherapy, infections and inflammatory aortic aneurysm.
Evaluation: CT or MRI, ESR and CRP, renal function, and IgG4 level. When the site or shape is atypical — for example tissue above the renal arteries, anterior displacement of the aorta or enlarged nodes — biopsy is needed to exclude lymphoma or tumour. PET-CT helps assess inflammatory activity and look for a malignant focus. The first treatment of obstruction is drainage: JJ stents or nephrostomy, to improve renal function.
Drug treatment of the idiopathic form: prednisone at 0.75 to 1 mg per kg per day with gradual tapering over months. As second line or for steroid sparing: mycophenolate, tamoxifen, and in IgG4-related disease — rituximab. When drug treatment fails or the stents cannot be removed, ureterolysis is performed — freeing the ureters from the tissue and moving them into the peritoneum or wrapping them in omentum. The disease recurs in some patients, so long-term imaging and laboratory follow-up is needed. It is important to stop a suspected drug.
Key points
- Tissue around the aorta that entraps the ureters.
- Bilateral hydronephrosis and a high ESR.
- About 70 percent idiopathic, partly IgG4.
- Drainage, then steroids.
- Biopsy when the picture is atypical.
Summary table
| Topic | Point | Note |
|---|---|---|
| Causes | Idiopathic (partly IgG4), drugs, malignancy, radiotherapy | About 70 percent idiopathic |
| Imaging | Cuff around the lower aorta, ureters drawn inward | CT or MRI |
| Biopsy | Atypical site or shape | Exclude lymphoma and tumour |
| Obstruction | JJ stents or nephrostomy | Improves renal function |
| Drug treatment | Prednisone 0.75 to 1 mg per kg per day | Second line: mycophenolate, tamoxifen, rituximab |
| Failure | Ureterolysis | Intraperitonealisation or omental wrap |
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Sources
- Vaglio A, Maritati F. Idiopathic Retroperitoneal Fibrosis (review, Journal of the American Society of Nephrology), 2016 — Diagnosis and treatment
- International Consensus Guidance Statement on the Management and Treatment of IgG4-Related Disease, 2015 — Retroperitoneal involvement
- Campbell-Walsh-Wein Urology, 12th edition (2020) — Management of Upper Urinary Tract Obstruction
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.