What Is Cystic Fibrosis–Related Arthritis (CFRA)?

Cystic fibrosis–related arthritis (CFRA) is a rare complication of cystic fibrosis (CF), a chronic, progressive genetic disorder that damages the lungs. When it is diagnosed in CF patients, it can be difficult to treat due to the medications they take for CF. There is no standard treatment plan because so little research has been done on CFRA.

But there are successful treatments for both CF and arthritis that help manage these conditions. If you have CF and are diagnosed with arthritis, your healthcare provider has the tools to create a treatment plan that will help slow down disease progression.

This article will discuss what CFRA is, how to diagnose it, what the treatment options are, and how this form of arthritis impacts people with CF.

What Is CFRA?

Arthritis is a joint disease that involves either inflammation or degeneration of the joints. These changes can cause pain, stiffness, and decreased range of motion when the joints are used.

There is no formal definition of CFRA. But if you have cystic fibrosis and begin to have symptoms of arthritis, you could be diagnosed with CFRA.

Types of CFRA

There are two types of CFRA: cystic fibrosis–related arthropathy (CFA) and hypertrophic pulmonary osteoarthropathy (HPO).

Signs and Symptoms of CFA

CFA is a common form of joint disease for CF patients, but it is unclear how frequently it occurs. It is estimated that between 2% and 8.5% CF patients develop CFA.

Signs of CFA include:

• Episodes of joint pain, swelling, or tenderness
• Limitation of movement
• Fever

CFA is more common in people with more severe lung disease and can get worse during an active lung infection.

Symptoms can develop gradually over the course of 12–24 hours and last for a few days. When these episodes go away, the pain usually clears up completely.

Signs and Symptoms of HPO

HPO happens when bones become thickened. It is slightly less common in CF patients, at between 2% and 7%.

Symptoms include:

• Episodes of joint pain
• Dull bone pain
• Digital clubbing (enlargement of fingertips)
• Worsening in cold weather

It is unclear what causes CFA and HPO. Very little research has been done on these conditions. Genetics could be a factor or it could be due to the tissue and organ damage CF causes.

Diagnosing CFRA

Diagnosing any type of arthritis can be challenging because there are several different types. The following tests are used to diagnose CFRA:

• Full blood count (also known as complete blood count, or CBC): This test measures your blood cell types and how many appear. This lets your healthcare provider determine if your blood is normal.
• Measuring acute phase reactant levels (APR): These are inflammation markers in the blood that increase during an infection or injury.
• X-rays: This imaging test will show changes in the bone.
• Synovial fluid analysis: This test allows your healthcare provider to see if the fluid between your joints is normal. They will examine the color, thickness, and if any bacteria are present.

More extensive testing may need to be done if multiple joints are involved.

CFRA Treatment

CFRA treatment can be complex because people with CF take strong medications to manage their condition. Sometimes, joint pain attacks may happen infrequently and resolve on their own. In this case, treatment may be limited to bed rest and NSAIDs (nonsteroidal anti-inflammatory drugs).

If these attacks start happening more often or last for more extended periods, you may be prescribed corticosteroids or DMARDs (disease-modifying antirheumatic drugs).

DMARDs and corticosteroids reduce inflammation and damage to joints by weakening your immune system. This interrupts the body's inflammation process, preventing more joint damage.

Common corticosteroids include prednisone, methylprednisolone, and cortisone. Types of DMARDs include Rheumatrex or Trexall (methotrexate), Imuran or Azasan (azathioprine), or Plaquenil (hydroxychloroquine).

Outlook

People with CF are living longer than they did in previous years thanks to new treatments and more funding for CF research. This means they will experience age-related complications, such as CFRA, that will require intense treatment. To have the best chance for successful management, consult with your CF care team if you experience joint pain or stiffness.

Summary

Cystic fibrosis–related arthritis (CFRA) is a complication of cystic fibrosis (CF). Like other types of arthritis, it involves joint pain, inflammation, and stiffness. Pain attacks can be infrequent or happen regularly.

There are two types of CFRA: cystic fibrosis–related arthropathy (CFA) and hypertrophic pulmonary osteoarthropathy (HPO). CFA is more episodic, with joint pain lasting less than one week at a time. Symptoms arise during flares (times when symptoms worsen) but may completely go away during episodes. HPO is less common and generally causes severe symptoms, including clubbing of the fingers and/or toes and long-term swelling of the bones and joints

Because there is so little research on CFRA, treatment may be similar to that for arthritis. This includes taking NSAIDs, oral corticosteroids, or DMARDs.

A Word From Verywell

Living with CF can be demanding. It affects multiple organ systems, particularly the lungs. Flare-ups can be challenging to manage. However, treatments have improved over the years, increasing life expectancy for people with CF. This means that along the way they could experience additional complications, like CFRA.

Bring any symptoms of arthritis that you have to the attention of your healthcare provider. If CFRA is caught early, your chances of successfully managing the condition will improve.