Retroperitoneal fibrosis is a very rare disorder. Scar tissue (fibrosis) develops in the flanks and lower back just behind the lining of the abdomen and pelvis (the retroperitoneum). The kidneys and their connection to the bladder (the ureters) are found there. So the scar tissue can block the ureters and causes serious problems such as kidney failure.

The condition is most common among people who are 40 to 60 years old. And it is twice as common in women as in men. There is an association with the use of certain medications (especially methysergide and beta-blockers), some cancers and vascular disease (for example, aortic aneurysm). Most of the time, doctors can’t find cause of it, especially in younger persons.

People with this condition often complain of vague back pain, poor appetite and fatigue. Sometimes they have fever, nausea and vomiting. Other symptoms may include leg swelling or pain because the blood vessels entering and leaving the legs are blocked.

The condition is not easy to diagnose early in its course. It progresses slowly and usually causes only mild and vague symptoms early on.

Treatment is not always helpful. But generally people receive corticosteroids and other immune-suppressing medicine (such as azathioprine) and surgery to unblock obstructed ureters. Sometimes a hollow tube (a stent) can be inserted into the ureter to keep it open and functioning. Drugs that might cause the condition should be discontinued.

If your daughter’s doctors suspect retroperitoneal fibrosis, imaging tests (such as CT scan or MRI) and biopsy are usually required to confirm the diagnosis.  And to exclude other causes of her problems.