Diagnosis of Psoriatic Arthritis.

History, symptoms and signs of psoriatic arthritis in a patient play an important role in diagnosing psoriatic arthritis. There are no specific tests to confirm diagnosis of this disease and tests that are done only serve the purpose of ruling out other causes of joint symptoms, such as rheumatoid arthritis and gout.

More posts on psoriatic arthritis.

1) What is psoriatic arthritis. 2) Types of psoriatic arthritis. 3) Symptoms of psoriatic arthritis 4) Causes, risks and complications 5) Diagnosis of psoriatic arthritis. 6) Treatment of psoriatic arthritis. 7) Self care and home remedies.

Physical Examination.

Certain findings on physical examination can give the doctor a fairly confirmed diagnosis of psoriatic arthritis.

• There may be history or symptoms of skin psoriasis. In 70% of the cases, skin psoriasis precedes psoriatic arthritis and in another 15% both the conditions come on at the same time. However, it is to be noted that patients with psoriasis can develop rheumatoid arthritis or osteoarthritis.
• A symmetrical pattern of joint inflammation on both sides of the body indicates psoriatic arthritis rather than rheumatoid arthritis.
• In psoriatic arthritis, nails may be found to be pitted or with lines. There also may be yellowish discoloration or they could be separated from the nail bed. These nail changes are seen in 80% of the cases of arthritis psoriasis. These nail changes are classical of psoriatic arthritis rather than other types of arthritis
• In psoriatic arthritis the distal most joints of the fingers closest to the fingertips are sometimes involved. This is typical and not seen in rheumatoid arthritis.
• More typical symptoms as explained under symptoms of psoriatic arthritis, that may be present are inflammation and pain of the Achilles tendon at the back of the heel, or planter fascia ( sole of the feet) and sausage like swelling of the fingers or toes (dactylitis).
• In 30% of the cases with psoriatic arthritis, conjunctivitis or pink eye is seen.

Laboratory Tests.

Certain blood tests for psoriatic arthritis are done to rule out other conditions.

Complete blood count.

This test will show elevated levels of ESR (indication inflammation) and anemia. This is just supportive and not conclusive because these results can be seen in many other conditions.

Rheumatoid factor (RF)

RF is an antibody that is present in patients with rheumatoid arthritis(RA) and not found in psoriatic arthritis. A negative RF test will help to rule out RA. However, RF test is positive in only 70% to 80% of RA cases and can also come positive in healthy individuals. Therefore it can be helpful but not conclusive.

Testing Joint Fluid (Arthrocentesis).

With the help of a long and fine needle, joint fluid is aspirated and tested for uric acid crystals. Presence of these crystals will indicate gout rather than arthritis psoriasis.

Blood marker test.

Blood test for genetic marker HLA-B27 is positive in 50% of psoriatic arthritis involving the spine.

Radiology Studies.

X-rays of the joints will reveal certain changes which can help suspect this form of arthritis. There will be injury of the bone and cartilage especially of the joints of the spine, hands and the sacroiliac joints. Bony erosions are typical. Changes seen in this condition differ from other forms of arthritis. These changes help a trained radiologist to conclude the possibility of psoriatic arthritis.

MRI

Magnetic resonance imaging or MRI gives a detailed picture of the bones and the soft tissues. This will especially help to detect inflammation o the ligaments and tendon of the feet and the lower back.

Bone density scan.

A bone density scan may be done to assess the loss of bone density which occurs in psoriatic arthritis. This is useful to know the risk of the patient to osteoporosis and fractures.

Related posts:

1. Psoriatic Arthritis.
2. Psoriatic Arthritis Causes, Risk Factors and Complications.
3. Types of Psoriatic Arthritis.
4. Symptoms and Signs of Psoriatic Arthritis.
5. Psoriatic Arthritis Treatments.
6. Living with Psoriasis and Psoriatic Arthritis.
7. Psoriatic Arthrtis|Self Care and Home Remedies.
8. How is Sleep Apnea Diagnosed.