Retroperitoneal fibrosis

Alternative names:

inflammation of the retroperitoneum

Definition:

A disorder involving a fibrous mass (aggregation of cells) in the back of the abdomen, which may occlude the ureters (the tubes that lead urine from the kidneys to the bladder)

Causes, incidence, and risk factors:

Retroperitoneal fibrosis is caused by a benign (noncancerous) fibrous mass that occurs in the retroperitoneal space (the back of the abdomen behind the abdominal lining). The cause is unknown.

The disorder is rare, involving about 5 out of 100,000 people, mostly men. The disorder may cause chronic unilateral obstructive uropathy or chronic bilateral obstructive uropathy as a result of ureteral occlusion caused when growth of the mass puts pressure on the ureters. The symptoms are caused by the obstruction of the ureters.