An early diagnosis and prompt treatment of psoriatic arthritis will prevent damage and deformity that can occur in the affected joint. The complication of this condition can be crippling and adversely affect the life of the patient. Disability can be permanent.
Though surgery is an option to treat severely damaged joints, it has a high complication and failure rate. Sometimes, it has to sacrifice mobility in order to give relief from pain to the patient.
How is Psoriatic Arthritis Diagnosed?
History of psoriasis, symptoms, and signs of psoriatic arthritis in a patient play an important role in diagnosing psoriatic arthritis. There are no specific tests to confirm the 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.
Medical history and symptoms
Certain findings on physical examination can give the doctor a confirmed diagnosis of psoriatic arthritis.
- There may be a 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, 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 develop pits or they have lines. There may also 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 that may be present include inflammation and pain of the Achilles tendon at the back of the heel, or plantar fascia (sole of the feet)
- There is sausage like swelling of the fingers or toes (dactylitis).
- In 30% of the cases with psoriatic arthritis, conjunctivitis, or pink eye is seen.
Laboratory blood tests
Certain blood tests advised to confirm psoriatic arthritis help 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 you see such results 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, the orthopedic doctor aspirates the joint fluid and tests it 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.
- X-rays of the joint will reveal certain changes that can help suspect this form of arthritis. They will show an injury to the bone and cartilage especially of the joints of the spine, hands, and 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.
- Magnetic resonance imaging or MRI gives a detailed picture of the bones and the soft tissues. This will especially help to detect inflammation of the ligaments and tendons of the feet and the lower back.
- Bone density scan. Because psoriatic arthritis leads to bone loss, a bone density scan may be done to assess the loss of bone density. This is useful to assess the patient’s risk of developing osteoporosis and fractures. A trained technician performs the scan using a DXA machine.
Psoriatic arthritis treatments
There is no cure for psoriasis and so also for arthritis psoriasis. Treatment aims to control the symptoms and complications and ease up the patient’s life. Early treatment is important as this disease can be disabling due to joint destruction if left untreated.
Since skin psoriasis and psoriatic arthritis exist together in most cases, treating symptoms of both becomes necessary. Treatment of psoriasis explains the cures prescribed for psoriasis.
Your doctor will use the following medications to treat psoriatic arthritis.
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Disease-modifying antirheumatic drugs
- Immunosuppressant medicines
- Biological modifiers or TNF-alpha inhibitors
Besides medications from your physician, you may require the services of a rheumatologist, physiotherapist, occupational therapist, and podiatrist.
1) Non-steroidal anti-inflammatory drugs (NSAIDs)
This is the first line of treatment for psoriatic psoriasis. Drugs such as ibuprofen and naproxen are given to reduce the pain, swelling, and stiffness of the joints. These may be followed by more potent drugs such as diclofenac, indomethacin, and etodolac if required.
In some patients, NSAIDs can cause irritation of the stomach, and the intestine and long-term use can result in gastrointestinal bleeding. Other more serious side effects include peptic ulcer, renal toxicity, cardiac toxicity, fluid retention, and hypertension.
However, many doctors prescribe Cytotec and omeprazole to protect the GI tract. Not everyone will need these medicines but you should look for any symptoms that reflect these side effects.
Prednisolone is the steroid used to control the severe inflammation that cannot be done with NSAIDs. It can be given orally or, in more severe and resistant cases, it can be injected directly into the joint or muscle to reduce the infection.
Steroids are given in the minimal required doses and tapered off gradually as they are associated with serious side effects such as diabetes, osteoporosis, cataract, joint weakness, and joint weakness. These steroids are different from the anabolic steroids that are used to build muscle and are banned in competitive sports.
3) Disease-modifying antirheumatic drugs (DMARDs)
Besides controlling the pain, swelling, and stiffness in the joints, these drugs also stop the progressive joint destruction which occurs in psoriatic arthritis. They are therefore indicated in cases that do not respond to NSAIDs and where NSAIDs do not control joint damage.
The only disadvantage is that these drugs act very slowly and it may take weeks or even months to see improvements.
Methotrexate is a commonly used DMARD. It has side effects which include kidney, liver, and lung damage. It is strictly contraindicated in pregnancy. Sulfasalazine is another drug that is used and shows some modest benefits.
4) Immunosuppressant medicines
Immunosuppressants are given to suppress the immune system, which is responsible for psoriasis and psoriatic arthritis. As a result of the suppressed immunity, your body becomes vulnerable to infections and diseases. These drugs are therefore reserved for use only in severe cases of psoriatic arthritis. They also cause damage to the liver and kidneys.
Commonly used immunosuppressants include
- Cyclosporines (Sandimmune and Neoral.)
- Azathioprine ( Azasan, Imuran)
- Leflunomide (Arava).
5) Biological response modifiers or TNF-alpha inhibitors
Biologics are the new type of drugss. They have been developed through the medical science of genetics using DNA technology.
They are manufactured proteins, which act by focusing on the specific function of the immune system that leads to psoriasis and not on the whole immune system.
They are administered either by the intramuscular or intravenous route.
Biological drugs include:
- Alefacept (Amevive). This drug acts by decreasing the number of activated T-cells of the immune system that are mainly responsible for the development of psoriasis.
- Etanercept (Enbrel)
- Infliximab (Remicade)
- Ustekinumab ( Stelera).
Etanercept, Infliximab, and Ustekinumab belong to the class of biologics, which are TNF alpha-blockers (Tumor necrosis factor). TNF are proteins that cause tumor cell necrosis and are pro-inflammatory agents. TNF alpha-blockers block the action of TNF.
Efalizumab (Raptiva) acts by blocking the activation of T cells and their migration to the skin. It has however, been withdrawn by the manufacturer in 2009.
These drugs have been associated with blood and nervous system disorders and certain cancers. More details are given under biologics.
6) Surgery for Psoriatic Arthritis
In cases where the psoriatic arthritis treatments aren’t enough and joint destruction is significant, joint replacement surgery is done to alleviate the pain, correct the joint disfigurement, and improve the performance of the joint.
According to a review published in the Journal of the American Academy of Orthopedic Surgeons in 2012, about 10 percent of people with psoriatic arthritis will need surgery to treat joint damage.
The most common surgeries for psoriatic arthritis are performed on the hand while hip and total knee replacement and hip and foot or ankle surgeries are less common.
Joint fusion or arthrodesis is usually preferred when the joints of the hands, ankle, or spine are damaged. The recovery period is about six months. However, ankle and spinal fusion surgeries require a 12-month recovery.
Synovectomy is another procedure that is done, which removes a large part of the synovium to help stop joint pain and prevent further joint destruction.
Synovium is a layer of membrane that produces the synovial fluid that lubricates the joint and facilitates its easy movement.
The orthopedic surgeon performs this surgery to remove inflamed joint tissue (synovium) that is causing intolerable pain and is limiting your joint mobility.