May 26, 2008

Diagnosis of Psoriatic Arthritis – Lab & Imaging Tests

Posted in Category : Bone, Joint & Muscles Disorders

Psoriatic arthritis is a type of arthritis that occurs concurrently with psoriasis of the skin. Psoriasis is a chronic skin condition that results in red patches all over the body. About 5% of all people affected by psoriasis develop arthritis and in most cases the psoriasis precedes the arthritis. The causes of psoriasis arthritis are still not known although scientists suspect a genetic link. What has been observed is that people with psoriasis have a much higher incidence of arthritis as compared to the general population.

The arthritis component of psoriatic arthritis may be mild, usually involving a few joints such as the fingers or toes. In severe cases, the disease will affect many joints including the spine. Such cases experience severe symptoms ranging from stiffness and pain to a burning sensation in the sacrum and lower spine. Skin and nail changes are also common with the psoriasis getting more severe after the onset of arthritis.

People with psoriasis should consult a doctor and follow their advice regarding dietary restrictions and treatment. This may help to delay or prevent the onset of arthritis.

A physical examination may reveal inflammation in the joints of the fingers, hands, knees, ankles, feet and toes. The inflammation will cause swollen and painful joints which may be warm to the touch. These symptoms will point towards a diagnosis of psoriatic arthritis. Early detection and treatment is very essential as the condition may result in serious and often crippling damage to the joints.

Once your doctor has taken your medical history and performed a physical examination, you may be required to undergo certain laboratory tests for psoriatic arthritis. The examination will focus on areas of your skin affected by psoriasis, with special attention being paid to the condition of your nails. Inflammation in the joints and other symptoms will also be taken into account.

Once the physical examination is complete, your doctor may call for certain tests. One of these is the ESR or erythrocyte sedimentation rate. Inflammation in the joints in cases of psoriatic arthritis may be elevated. Other blood tests may also be performed. Levels of serum uric acid will be tested, which if raised, may suggest psoriatic arthritis as the cause.

Another blood test that may be performed is one to check for the genetic marker HLA-B27. This test is positive in about half of all those suffering from psoriatic arthritis with inflammation of the spine. Other tests may be performed to rule out the possibility of other forms of arthritis such as rheumatoid arthritis.

If the knee or other major joints are affected, a procedure known as arthrocentesis may be carried out. During this procedure, a sterile needle is inserted into the affected joint and fluid from the joint is aspirated. The fluid is then analyzed for signs of uric acid crystals, infection or other inflammatory conditions.

Imaging tests using x-rays, MRI (magnetic resonance imaging) scans or CT (computerized tomography) scans may also be performed to aid in a diagnosis of psoriatic arthritis. These imaging tests can help reveal any changes to the cartilage or bone in the different joints.

Treatment for this condition usually involves the use of medications to control inflammation and pain. Medications prescribed may include non-steroidal anti-inflammatory drugs or NSAIDs, disease-modifying anti-rheumatic drugs or DMARDs or newer medications such as adalimumab (Humira) or etanercept (Enbrel). On occasion, steroids may be injected into the affected joints to reduce inflammation and pain. On rare occasion, surgery to repair or replace the damaged joint may be undertaken.

Along with these measures you will also be advised to undergo physical therapy as well as rest. Dietary changes may also be suggested.

The prognosis for this disease is good especially if detected and treated early. Pain and inflammation are usually relieved by medications but it is imperative that you follow your doctor’s advice with regard to diet, exercise, lifestyle and medication.