Retroperitoneal fibrosis occurs when extra fibrous tissue forms in the area behind the stomach and intestines. The tissue forms a mass (or masses) or tough fibrotic tissue. It can block the tubes that carry urine from the kidney to the bladder.
The cause of this problem is mostly unknown. It is most common in people aged 40 to 60. Men are twice as likely to develop the condition as women.
Retroperitoneal fibrosis is a rare disorder that blocks the tubes (ureters) that carry urine from the kidneys to the bladder.
Exams and Tests
Abdominal CT scan is the best way to find a retroperitoneal mass.
Other tests that can help diagnose this condition include:
- BUN and creatinine blood tests
- Intravenous pyelogram (IVP), not as commonly used
- Kidney ultrasound
- MRI of the abdomen
- CAT scan of the abdomen and retroperitoneum
A biopsy of the mass may also be done to rule out cancer.
The outlook will depend on the extent of the problem and the amount of damage to the kidneys.
The kidney damage may be temporary or permanent.
The disorder may lead to:
- Ongoing blockage of the tubes leading from the kidney on one or both sides
- Chronic kidney failure
Try to avoid long-term use of medicines that contain methysergide. This drug has been shown to cause retroperitoneal fibrosis. Methysergide is sometimes used to treat migraine headaches.
- Dull pain in the abdomen that increases with time
- Pain and change of color in the legs (due to decreased blood flow)
- Swelling of one leg
- Decreased urine output
- No urine output (anuria)
- Nausea, vomiting, changes in mental status caused by kidney failure and build-up of toxic chemicals in the blood
- Severe abdominal pain with hemorrhaging (due to death of intestinal tissue)
Corticosteroids are tried first. Some health care providers also prescribe a drug called tamoxifen.
If corticosteroid treatment does not work, a biopsy should be done to confirm the diagnosis. Other medicines to suppress the immune system can be prescribed.
When medicine does not work, surgery and stents (draining tubes) are needed.
When to Contact a Medical Professional
Call your health care provider if you have lower abdomen or flank pain and less output of urine.
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