Retroperitoneal fibrosisN13.5

Ormond 1948

Rare, chronic, autoimmunologic, fibrosing retroperitoneal inflammation leading to muralization of the abdominal aorta, iliac arteries, and ureters. Similar fibrosing disease is found in the eyes, thyroid, pancreas, mediastinum, and bile ducts (Urban ML et al 2015). The disease can also occur in multiple organs simultaneously and is then referred to as multifocal idiopathic fibrosclerosis.

Idiopathic form (primary form); about 70% of cases.

• In primary (also known as Albarran-Ormond syndrome) retroperitoneal fibrosis, no underlying disease or other precipitating event can be demonstrated. The condition is classified as an autoimmune IgG4-associated disease (Urban ML et al. 2015) and may be associated with diverse organ involvement e.g., autoimmune pancreatitis (Fujimori N et al. 2013)

Secondary form: secondary retroperitoneal fibrosis may be associated with other diseases:

• Crohn's disease
• Infections (tuberculosis, syphilis),
• systemic lupus erythematosus
• primary biliary cholangitis
• granuloma faciale
• granulomatosis with polyangiitis
• Sjögren's syndrome
• Erdheim-Chester disease.
• Arteriosclerosis of the aorta or aortic aneurysm.

Other initiating factors include:

• X-ray irradiation
• Exposure to asbestos
• Chronic urinary retention
• Inflammation or infection of the urinary tract
• Injuries
• Malignant tumorous processes
• Medications (vasoactive drugs such as methysergide, pergolide, or bromocriptine).

Symptoms vary with the stage of the disease. In an early phase of the disease, belt-like pain in the lumbar region or in the back is usually felt. The pain is independent of body position and physical activity, but becomes more and more severe as the disease progresses. In addition, there is a general feeling of illness, reduced performance and weight loss.

As the fibrotic inflammatory process spreads, it eventually leads to the walling of the ureter, veins, nerves and arteries. This results in additional flank pain, restriction of kidney function, leg vein thrombosis, and pain and swelling in the leg (Tzou M et al. 2014).

ESR and CRP elevated; ANCA pos. (60% of cases); IgG4 in serum often elevated.

The suspected diagnosis is usually made on the basis of computer tomography or sonography of the abdominal cavity. Further clarification by magnetic resonance imaging, excretory urography. Histological backup.

First clinical signs are often (the late manifested) nephrogenic complications such as the walling of the ureter with urinary retention. In this often emergency stage of the disease, splinting of the ureter with a catheter is used as an acute measure. Otherwise, the previously favoured surgical debulking approach (Scheel PJ Jr et al. 2013) takes a back seat in favour of long-term immunosuppressive therapy. There is a good and prompt response to an immunosuppressive therapy with glucocorticosteroids (prednisolone; initial dose 30-40mg/day - Fujimori N et al. 2013); furthermore additive mycophenolate. Alternatively: MTX, azathioprine, cyclophosphamide, tamoxifen.

1. Bledsoe JR et al. (2018) IgG4-related disease: review of the histopathologic features, differentialdiagnosis, and therapeutic approach. APMIS 126:459 476.
2. Fujimori N et al. (2013) Retroperitoneal fibrosis associated with immunoglobulin G4-related disease. World J Gastroenterol 19:35-41.
3. Gómez Rivas J et al.(2020) Retroperitoneal fibrosis: A literature review. Arch Esp Urol 73:60-67.
4. Herta T et al. (2018) IgG4-associated cholangitis - clinical presentation of an overlooked disease entity. Internist (Berl) 59:560-566.

5. Scheel PJ Jr et al (2013) Retroperitoneal fibrosis. Rheum Dis Clin North Am 39:365-81.

6. Tzou M et al (2014) Retroperitoneal fibrosis. Vasc Med 19:407-414.

   Urban ML et al. (2015) Idiopathic and secondary forms of retroperitoneal fibrosis: a diagnostic approach. Rev Med Internal 36:15-21.