Retroperitoneal Fibrosis

Retroperitoneal fibrosis is a rare condition where scar-like tissue grows behind the abdominal cavity, potentially squeezing vital organs like the ureters, kidneys, and major blood vessels. While most cases have no known cause, early diagnosis and treatment can lead to full recovery for many patients.

Table of contents

• What is Retroperitoneal Fibrosis?
• Other Names for This Condition
• Organs and Structures Affected
• How Common is This Condition?
• Signs and Symptoms
• What Causes Retroperitoneal Fibrosis?
• Who is at Risk?
• Possible Complications
• How Doctors Diagnose This Condition
• Treatment Options
• Outlook and Recovery
• Prevention

What is Retroperitoneal Fibrosis?

Retroperitoneal fibrosis is a rare disease that causes scar-like tissue to develop in a space behind your abdominal cavity called the retroperitoneum, which is the area behind the membrane that surrounds your digestive organs^[1]. This condition is also known as Ormond’s disease, named after John Ormond, an American doctor who described cases of this condition in 1948^[2].

The disease involves chronic inflammation and the growth of fibrous tissue in this space. Fibrosis is the growth of excess connective tissue, which forms masses that can surround and squeeze nearby organs and blood vessels^[3]. As the condition progresses, this tissue can wrap around important structures and cause them to become compressed or blocked.

The fibrotic process typically starts around the aorta, which is the large blood vessel that carries blood from your heart to the rest of your body^[4]. The condition is considered immune-mediated, meaning your immune system may play a role in causing it^[2].

Ormond’s disease, Ormond disease

Organs and Structures Affected

The retroperitoneal space contains several vital organs and structures that can be affected by this condition. Understanding which parts of your body are at risk helps explain the symptoms and complications that may arise.

• Ureters (tubes that carry urine from kidneys to bladder)
• Kidneys
• Aorta (main artery from the heart)
• Vena cava (large vein returning blood to the heart)
• Adrenal glands
• Bladder
• Intestines

The ureters are the most commonly affected organs in retroperitoneal fibrosis. These are two tubes that take urine from your kidneys to your bladder^[1]. When the fibrous tissue surrounds and squeezes these tubes, it can block the flow of urine, leading to kidney swelling and potential damage.

How Common is This Condition?

Retroperitoneal fibrosis is very rare. Studies estimate that it occurs in approximately 1 in 200,000 to 500,000 people per year^[4]. Another study from the Netherlands estimated the incidence at about 1.3 in 100,000^[11].

The condition occurs approximately twice as often in men as it does in women, though the reason for this difference is not clear^[4]. It most frequently appears in people between the ages of 40 and 60, although it can occur at any age^[1][4].

Signs and Symptoms

The symptoms of retroperitoneal fibrosis can vary greatly from person to person, depending on where the fibrous tissue develops and how severe it becomes. Some people may not have any symptoms at all, especially in the early stages^[1].

In the early stages, the most common symptom is dull pain that may be hard to pinpoint exactly. You might feel this discomfort in your belly, lower back, or sides^[1][2]. If you have testicles, it’s common to feel pain there as well^[1]. The pain typically increases gradually over time^[3].

As the condition progresses, additional symptoms may develop:

• Low urine output or difficulty urinating^[1]
• Fatigue and feeling generally unwell^[1]
• Leg swelling, pain, or color changes^[1]
• Difficulty moving your legs^[1]
• Swelling in the scrotum^[1]
• Weight loss^[3][7]
• Fever or night sweats^[7]
• Loss of appetite^[7]
• Nausea^[7]
• Feeling thirstier than usual^[3]

It is quite common for pain, weight loss, lack of energy, and sweats to occur together^[7]. You should contact your doctor if you experience pain in your flank or lower abdomen, or if you notice you are urinating much less than usual^[3].

What Causes Retroperitoneal Fibrosis?

In most cases of retroperitoneal fibrosis, doctors cannot identify a specific cause. Approximately 70% of cases are idiopathic, which means the cause is unknown^[2][5]. This is sometimes called idiopathic retroperitoneal fibrosis.

Researchers believe that an abnormal immune system response may be involved in many cases. The immune system may be reacting abnormally to blood vessels damaged by fatty buildup (a condition called atherosclerosis), or to certain drugs, infections, or trauma^[4]. Many of these previously unexplained cases are now thought to be related to IgG4-related disease, an autoimmune disorder^[6].

When a cause can be identified, it may include:

• Certain medications^[1]
• Cancer, including Hodgkin and non-Hodgkin lymphoma^[1]
• Fibroinflammatory disorders^[1]
• Infections like tuberculosis^[1]
• Radiation therapy^[1]
• Tissue damage from trauma or surgery^[1]

Several types of medications have been linked to retroperitoneal fibrosis. These include beta-blockers used for heart disease (such as propranolol, metoprolol, and atenolol), dopamine antagonists that treat mental health disorders and nausea, hydralazine tablets for high blood pressure, migraine medications like ergotamine tablets, and certain pain medications^[1].

The condition occasionally occurs with autoimmune disorders, which happen when the immune system malfunctions and attacks the body’s own organs and tissues^[4]. Retroperitoneal fibrosis has been associated with various conditions including connective tissue diseases, inflammatory bowel disease, autoimmune thyroiditis, and several other autoimmune conditions^[6].

Who is at Risk?

Several factors can increase your risk of developing retroperitoneal fibrosis. The condition most commonly occurs in males between 40 and 60 years old, though it can affect people of all ages and genders^[1].

Exposure to asbestos and tobacco product use are significant risk factors. Research shows that having both of these exposures can increase your risk even more than having just one. The good news is that avoiding even one of these risk factors can reduce your overall risk^[1][6].

A connection has been identified with the HLA-DRB1 gene, suggesting that genetics may play a role^[11]. However, most cases occur randomly rather than running in families. In rare instances, the condition has been reported in a few members of the same family, but whether it can be inherited is not clear^[3][4].

Possible Complications

When retroperitoneal fibrosis is advanced or left untreated, it can lead to serious, potentially life-threatening complications^[1]. These complications occur because the fibrous tissue compresses and blocks important organs and blood vessels.

Complications that may develop include:

• Kidney failure^[1]
• Low red blood cell count (anemia)^[1]
• Inability to urinate (anuria)^[1]
• High blood pressure^[1][2]
• Jaundice (yellowing of the skin)^[1]
• Nausea and vomiting^[1]
• Nervous system issues^[1]
• Tissue death in the intestines^[1]
• Unplanned weight loss^[1]
• Blood clots and deep venous thrombosis^[1][7]

Blockage of the ureters is the most common complication, which can lead to kidney swelling and impaired kidney function^[2]. When kidneys fail, toxic substances build up in the blood and tissues, causing additional problems^[4]. Obstruction of blood flow to and from the legs can result in pain, color changes, and swelling in the limbs^[4].

These complications underscore why long-term follow-up by a specialist team is important, even if you feel well^[7].

How Doctors Diagnose This Condition

Diagnosing retroperitoneal fibrosis requires a high degree of suspicion because the symptoms and laboratory findings are often nonspecific^[5]. Many cases are discovered incidentally during imaging studies performed for other reasons^[2].

Your doctor will start with a physical examination, which may include pressing on your belly to check for abnormal masses^[1]. Healthcare providers often diagnose this condition using a combination of blood tests and imaging studies^[1].

Blood tests may show several abnormalities. The erythrocyte sedimentation rate (a measure of inflammation) is often elevated^[5]. C-reactive protein levels may also be elevated^[5]. Blood tests can detect early signs of kidney disease or issues like anemia^[1]. Urea and creatinine levels, which indicate kidney function, may be elevated^[5].

Imaging tests are essential for diagnosis. Your provider may use:

• Kidney ultrasound to assess fibrosis, blockage, and other issues if symptoms suggest kidney disease^[1]
• CT scan or MRI to measure fibrosis severity and show how well your kidneys are working (these are the preferred imaging methods)^[1][6]
• Nuclear medicine imaging^[1]
• Pyelogram, a special X-ray of your urinary system, to show blockages^[1]

CT scanning is the most frequently used imaging method for diagnosis and follow-up of retroperitoneal fibrosis. On CT, doctors can see a mass surrounding the aorta and common iliac arteries^[6]. MRI can also provide detailed images and show the characteristics of the fibrous tissue^[6].

A biopsy, which involves taking a small tissue sample for examination, may be required in some cases^[2]. This is usually done as a day-case procedure using a scanner to guide a needle into the affected area^[7]. You may need a biopsy if treatments don’t work, if your provider has concerns about cancer, or if the location of fibrosis is atypical^[1][6].

An important part of the diagnostic process is ruling out secondary causes of retroperitoneal fibrosis, such as malignancy, infection, medications, or previous injury to the retroperitoneal area^[5].

Treatment Options

Treatment for retroperitoneal fibrosis depends on several factors, including the severity of the condition, what caused it, how much damage has occurred, and whether complications have developed^[3]. The best care requires an integrated approach that may combine medications and surgery^[9].

The main goals of treatment are to slow down the inflammation and scarring process, protect kidney function, reduce pain, and avoid complications^[7]. Each case is different, and treatment options need to be discussed in detail between you and your medical team^[7].

Medical Treatment

For acute relief of ureter blockage, doctors commonly combine drug therapy with the insertion of a double pigtail stent (DJ stent) or a percutaneous nephrostomy (PCN), which are tubes that help drain the kidneys^[11].

Medications that dampen down the immune system are often used when an overactive immune system is thought to be the underlying cause. The most common medical treatment involves corticosteroids (also called steroids), such as prednisolone^[2][7]. A standard approach is to start with a higher dose (40-60 mg per day) and gradually reduce it to 10 mg per day within 2-3 months, then discontinue after 12-24 months^[9].

Research studies suggest that steroids can reduce the size of the fibrotic mass by around 50% in up to 95% of cases^[7]. However, this must be balanced against the risk of long-term steroid side effects, which can include weight gain, diabetes, fragile skin, and weakened bones^[7].

Other immunosuppressive medications may be used in combination with steroids or as alternatives. These include azathioprine, mycophenolate mofetil (MMF), methotrexate, cyclophosphamide, and rituximab^[9][11]. The combination of corticosteroids and azathioprine is particularly useful in patients with signs of inflammation^[9].

Tamoxifen, a medication typically used for breast cancer, has shown benefit in various studies, although exactly how it works for this condition remains unclear^[6][9].

A comprehensive review of treatment approaches found that across different types of medical therapy, outcomes were generally good, with high rates of improvement and relatively similar effectiveness among different drug options^[11]. This suggests that treatment choice should depend on factors such as potential side effects, your other medical conditions, and your doctor’s expertise^[11].

Surgical Treatment

Surgery may be necessary in some cases, particularly when there is severe urinary tract obstruction^[6]. Surgical procedures can help free the ureters from the surrounding fibrous tissue^[7].

When surgery is combined with steroid treatment, studies show it can reduce the rate of ureter re-narrowing from 48% to 10%^[9].

Lifestyle Measures

A healthy lifestyle is important for all individuals with retroperitoneal fibrosis, especially since blood vessel disease may drive the condition in some cases. This includes regular mild exercise, achieving ideal body weight, avoiding smoking, and following a nutritious diet^[7]. Your specialty doctors and general practice should be able to advise and help with adopting these healthier habits^[7].

Outlook and Recovery

Most people with retroperitoneal fibrosis can lead normal lives with proper treatment^[7]. With early diagnosis and treatment, most people make a full recovery^[1].

The timeline for improvement depends on how severe your condition was when treatment started and how long you had the condition. Healing of the kidneys typically begins by the second week of treatment^[3]. The condition rarely progresses to complete kidney failure requiring a kidney transplant^[3].

However, retroperitoneal fibrosis is a long-term condition. There can be periods when the disease becomes inactive, but it may later reactivate^[7]. Studies report recurrence rates of around 18% across different treatment approaches^[11]. Most recurrences occur within 12 months, and some respond to restarting treatment^[9].

This is why long-term follow-up by a specialist team is important. Complications such as kidney disease and high blood pressure may not cause symptoms until very late, but they can be identified and treated if caught early^[7].

Prevention

While you cannot always prevent retroperitoneal fibrosis, especially when the cause is unknown, there are steps you can take to reduce your risk.

The most important preventive measure is avoiding known risk factors when possible. This includes not smoking or using tobacco products and avoiding exposure to asbestos^[6]. Research shows that these are strong risk factors that work together to increase risk, so avoiding even one of them can significantly reduce your chances of developing the condition^[1].

If you are taking medications that have been linked to retroperitoneal fibrosis, discuss the risks and benefits with your doctor. However, do not stop taking prescribed medications without talking to your healthcare provider first.

For people already diagnosed with the condition, following your treatment plan and attending regular follow-up appointments can help prevent complications and catch any problems early^[7].