Understanding Cystic Fibrosis Associated Arthritis

As cystic fibrosis patients are surviving longer into their adult years and “middle age,” some may find themselves experiencing episodes of arthritis. Although cystic fibrosis associated arthritis has been observed to affect only 5-10% of the cystic fibrosis population, there’s no denying it happens.

Aches and pains of the joints and particularly large joints such as knees and ankles can cause extreme pain. During an episode, these sites may feel warm to the touch as well as appear swollen and red. Flu-like symptoms such as fatigue and fever may also be present. The interesting thing about cystic fibrosis related arthritis is that flare-ups are rather intermittent; patients typically experience no other symptoms in between episodes.

Defining CF Associated Arthritis

Cystic fibrosis associated arthritis (CFAA)is described as having episodes that last less than a week, involve the large joints (ankle, knee, wrist, shoulder) and responds to treatment with anti-inflammatory medication.

Non-arthritic Joint Pain

Since CF patients are often malnourished and have osteopenia or osteoporosis, aches and pains may not necessarily be from arthritis, but rather from a condition called hypertrophic pulmonary osteopathy (HPOA.) HPOA is not specifically tied to CF, but is observed in other lung diseases. HPOA is believed to be the culprit behind finger clubbing.

Diagnosis

Diagnosis cystic fibrosis associated arthritis can only be diagnosed once other likely possibilities for joint pain have been ruled out. A doctor will ask questions about when the symptoms appeared, whether the pain was the same on both sides of the body, and whether a rash or fever was present. The doctor also needs to know approximately how long the episodes of pain last. It is important for the patient to distinguish whether the pain is sharp or dull, throbbing or steady.

Treatment

As with most inflammatory conditions, non-steroidal anti-inflammatory (NSAID) medications are the first course of action. Ibuprofen in prescription strength doses (i.e., 600mg or greater) is usually enough to gain control over an episode cystic fibrosis associated arthritis. There is a small percentage of people with CF-associated arthritis that are resistant to NSAID treatment, but do respond to corticosteroids such as prednisone. An anti-inflammatory diet may also be helpful to lessen the severity of an episode and prevent further ones.

DEXA Scans

Over the last decade, CF researchers and physicians have observed that as patients with CF age, their metabolic rate (i.e. how much energy the body uses) changes are disease severity increases. Malabsorption issues are closely linked with poor performance on pulmonary function tests. It is of utmost importance that CF patients and their clinics work hard to maintain adequate nutritional status.

People with cystic fibrosis, especially those who are diagnosed as having pancreatic insufficiency, have great difficulty absorbing vital minerals and nutrients from food. Doctors regularly prescribe vitamin and mineral supplements for CF patients with the expectation and hope that semi-normal levels of these can be attained in the body.

Without sufficient concentrations of certain vitamins and minerals in the body, a patient with CF may develop bone density problems. As the number of patients exhibiting weak bones has increased, there is an added emphasis being placed on the necessity of what are called DEXA scans.

DEXA (dual energy x-ray absorptiometry) scans should be performed every three years to measure bone mineral density.

The procedure of a DEXA scan is painless and simple. The patient lies on his/her back on an examination table under a scanner arm. The scanner then uses x-ray beams from two different directions to the patient’s body. The energy from the x-rays travels at a particular frequency, and is transmitted to a receiver that determines how quickly it moved through the bone. It does this by counting photons, which are energy particles. In places where the bone is denser, the x-ray beam slows down. By measuring these rates of transmission, overall bone density is calculated.

A computer takes the information about the number of photons and compares it to a normal, expected value. The result is called a “T” score. Different T scores can tell a doctor whether a patient is at risk for developing osteoporosis, or is perhaps exhibiting osteopenia.

The entire DEXA scan procedure only takes 4 minutes to scan the entire body. Since the test is performed annually, the CF team can identify problems with mineral density and work with a patient to take preventive measures to prevent bone loss. Calcium supplements with D vitamins added are commonly prescribed. Vitamin D, which is a fat soluble vitamin, is directly responsible for how much calcium comprises the bones in the body.

Many people have heard of osteoporosis, but osteopenia is not as commonly known. Osteopenia is when a person's bones are less dense than normal. Eventually it could lead to osteoporosis. Typically people who develop this condition are much older and are likely to be post-menopausal women. Bone density losses take place more frequently as people age. However, people with CF are likely to be diagnoses with osteopenia or osteoporosis at younger ages.. Without sufficient vitamin D and calcium to build strong bones, the risk of developing osteoporosis or osteopenia increases.

Other things that can help a patient safeguard his/herself against future problems with bone mineralization includes the following:

• eat a diet rich in calcium and vitamin D
• limit caffeine intake
• limit alcohol consumption
• do weight-bearing exercise like running, walking, or hiking (basically anything that forces my body to work against gravity)
• take care of mental health issues so that they don't adversely affect physical health
• sit in the sun for about 15 minutes per day to give the body the opportunity to make its own vitamin D

For more information please visit the following links:

Nutritional Problems in CF
Post-Transplant Osteoporosis in CF
Prepubertal Bone Mineral Accretion
Study of Benefits of Growth Hormone for CF