Causes

Retroperitoneal fibrosis is a rare disorder that occurs when extra fibrous tissue forms in the area behind the stomach and intestines. The excess tissue forms a mass (or masses) that can block the tubes that carry urine from the kidney to the bladder. Doctors don't know why these masses form. It is most common in people aged 40 - 60. Men are twice as likely to develop the condition as women.

Symptoms

Early symptoms:

• 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

Later symptoms:

• Decreased urine output
• No urine output (anuria)
• Nausea, vomiting, changes in thinking caused by kidney failure and build-up of toxic chemicals in the blood
• Severe abdominal pain with hemorrhaging (due to death of intestinal tissue)

Exams and Tests

Abdominal CT scan is the best method to reveal a retroperitoneal mass.

Other tests that can help diagnose this condition include:

• BUN and creatinine blood tests
• Intravenous pyelogram (IVP)
• Kidney ultrasound
• MRI of the abdomen

A biopsy of the mass may also be done to rule out cancer.

Treatment

Powerful anti-inflammatory medicines called corticosteroids are tried first. Some doctors also use a drug called tamoxifen to treat this condition.

If corticosteroid treatment doesn't work, a biopsy should be done to confirm the diagnosis. If confirmed, other medicines to suppress the immune system are usually prescribed.

When medicine does not work, surgery and stents (draining tubes) are needed.

Outlook (Prognosis)

Prognosis depends on the extent of the fibrosis and the amount of damage to the kidneys. The kidney damage may be temporary or permanent.

Possible Complications

The disorder may lead to:

• Chronic bilateral obstructive uropathy
• Chronic kidney failure
• Chronic unilateral obstructive uropathy

When to Contact a Medical Professional

Call your health care provider if you experience lower abdomen or flank pain, particularly with decreased urine volume.

Prevention

If possible, avoid long-term use of medications that contain methysergide, which has been shown to cause retroperitoneal fibrosis. Methysergide is sometimes used to treat migraine headaches.

Alternative Names

Idiopathic retroperitoneal fibrosis; Ormond's disease

References

Rottenberg G, Sandhu C. Radiology of the upper urinary tract. In: Adam A, Dixon AK, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 41.

Turnage RH, Richardson KA, Li BD, McDonald JC. Abdominal wall, umbilicus, peritoneum, mesenteries, omentum, and retroperitoneum. In: Townsend CM, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2008:chap 43.

Pais VM, Strandhoy JW, Assimos DG. Pathophysiology of urinary tract obstruction. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 37.

Hsu THS, Streem SB, Nakada SY. Management of upper urinary tract obstruction. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 38.

Update Date: 3/17/2012

Reviewed by: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Louis S. Liou, MD, PhD, Chief of Urology, Cambridge Health Alliance, Visiting Assistant Professor of Surgery, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.