Idiopathic Retroperitoneal Fibrosis is a rare disorder involving the formation of a fibrous mass of tissue in the hollow space at the back of the abdomen. The fibrous mass can affect the flow of urine to the kidneys and may also affect other abdominal organs.

 

There proliferation of fibrous tissue in the retroperitoneal, the compartment of the body containing the kidneys, aorta, bile duct and renal tract and various other structures.

Causes

60% to 70% of cases of retroperitoneal fibrosis are idiopathic

• Malignancy- lymphomas, sarcomas, and many carcinomas, including carcinomas of the breast, lung, stomach, colon, bladder, prostate, and cervix
• Severe atherosclerosis
• Aortic aneurysms
• Chronic retroperitoneal inflammation
• Retroperitoneal trauma
• Autoimmune disease
• Irradiation
• Certain drugs (eg, beta-blockers, methysergide, bromocriptine, methyldopa, hydralazine, ropinirole)

Immune-mediated connective-tissue diseases in retroperitoneal fibrosis includes

• Ankylosing spondylitis
• Systemic lupus erythematosus
• Rheumatoid arthritis
• Scleroderma
• Riedel thyroiditis
• Immune complex membranous glomerulonephritis

Signs and symptoms

• Lower back pain and abdominal pain
• Dull, poorly localized, noncolicky pain in the flank, back, scrotum, or lower abdomen
• Reduced urination
• Ureteric colic
• Hematuria,
• Decreased urinary frequency
• Fever
• Lower-extremity edema
• Phlebitis, and deep venous thrombosis
• Volume-dependent hypertension
• Swelling of one leg
• Decreased circulation in the legs leading to pain and discoloration
• Total lack of urine (anuria)

Complications

• Renal failure
• Ureteric obstruction
• Pyrexia of unknown origin
• Hydronephrosis
• Systemic hypertension 

 

Tests and diagnosis

• Elevated ESR, normocytic normochromic anemia, and raised C-reactive protein level
• Raised urea and creatinine levels (50%-75%)
• Polyclonal hypergammaglobulinemia
• Alkaline phosphatase
• Antinuclear antibodies
• Microscopic hematuria and puyuria on urine examination
• Plain abdominal radiography reveal enlarged renal outline due to Hydronephrosis
• Chest X-ray may demonstrate pulmonary edema or fibrosis
• CT abdominal scanning is the most frequently used imaging method for diagnosis and follow-up of retroperitoneal fibrosis.

Treatment

• In the absence of severe urinary tract obstruction (which generally requires surgery with omental wrapping), treatment is generally with glucocorticoids.
• Tamoxifen, a nonsteroidal antiestrogen, is used in the treatment of retroperitoneal fibrosis.
• Compared with steroids, the adverse effect profile of tamoxifen is low; thus, clinicians consider tamoxifen a reasonable treatment option.
• Immunosuppressive agents- Mycophenolate mofetil or Azathioprine has been used when steroid therapy has failed and as a steroid-sparing drug to block the proliferation of T cells and B cells

Surgical care

Primary management of retroperitoneal fibrosis consists of open biopsy, ureterolysis, and lateral/intraperitoneal transposition or omental wrapping of the involved ureters.

Percutaneous nephrostomy or ureteral stenting are recommended as temporary measures in the presence of obstructive uropathy.