Idiopathic retroperitoneal fibrosis

Idiopathic retroperitoneal fibrosis (IRF) is a sub type of retroperitoneal fibrosis where no obvious cause is found. It includes a spectrum of diseases which are characterized by fibro-inflammatory tissue surrounding the abdominal aorta and the iliac arteries. This process may extend into the retroperitoneum often enveloping the surrounding structures like ureters. 

Retroperitoneal fibrosis in general is an uncommon condition with an estimated incidence of about 1.38 cases per 100,000 people 1. Of this about 70% cases are idiopathic.

This inflammatory pathology is thought to arise as an autoimmune response to ceroid which leaks out of the atherosclerotic plaques and causing vasculitis. It is seen in association with other autoimmune processes, suggesting possibility of an autoimmune underlying pathology.


Reported associations include

Contrast enhancing fibrosis encompassing the retroperitoneal structures causing uretric and vascular obstruction and displacement is seen with no other demonstrable alternative conditions or malignancy.

Complications such as acute renal failure secondary to periureteral involvement require prompt intervention. Treatment usually involves corticosteroids with or without other immunomodulating medications or tamoxifen. In the presence of periureteral or perivascular involvement, surgical intervention may be necessary.

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Article information

rID: 25643
Section: Pathology
Synonyms or Alternate Spellings:
  • Primary retroperitoneal fibrosis
  • Idiopathic retroperitoneal fibrosis (IRF)

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