How to say it

sor-ee-A-tihk

ar-THRI-tihs

What causes psoriatic arthritis?

Healthcare providers don’t know what causes this condition. But a child’s immune system, genes, and the environment may play a role. Children with this health problem often have a family member with arthritis or psoriasis.

Symptoms of psoriatic arthritis

The skin condition psoriasis may start before or after the arthritis. Psoriasis causes a scaly, red, itchy rash. This rash may occur on the knees, elbows, scalp, face, and the folds of the buttocks. It can also cause pitting of fingernails or toenails. 

Each child’s symptoms may vary. Symptoms may include:

• Inflamed, swollen, and painful joints, often in the fingers and toes

• Morning stiffness in the joints

• Reddened skin over the affected joints

• Sausage-like swelling of fingers and toes, plus swollen wrists (more common in girls ages 1 to 6)

• Deformed joints from chronic inflammation

• Symptoms in the spine or sacroiliac joint (more common in older children)

• Tenderness in tendons, such as the Achilles tendon

• Eye pain

• Lack of energy (fatigue)

• Obesity (higher risk)

Diagnosing psoriatic arthritis

Psoriatic arthritis is easier to confirm if your child already has psoriasis of the skin. If the skin symptoms have not yet occurred, diagnosis is harder. Your child’s healthcare provider will ask about your child’s past health. They will give your child a physical exam. Your child may have blood tests, such as:

• Erythrocyte sedimentation rate (ESR). This is also called sed rate. This test looks at how quickly red blood cells fall to the bottom of a test tube. When swelling and inflammation are in the body, the blood's proteins clump together. They become heavier than normal. They fall and settle faster at the bottom of a test tube. The faster the blood cells fall, the more severe the inflammation.

• Uric acid. High blood uric acid levels are linked to psoriatic arthritis.

• Complete blood count (CBC).  This test checks for levels of red blood cells (anemia), white blood cells, and platelets. Platelet levels are likely to be high.

• Antibody blood tests. These tests are done to look for certain kinds of proteins called antibodies. These tests can be positive for many kinds of rheumatic diseases. Younger children are more likely to have a positive antibody test. 

Other tests may include:

• X-rays. This test uses a small amount of radiation to make images of organs, bones, and other tissues. Sometimes more advanced X-rays, such as an MRI scan, is needed.

• Eye exam. This is done by a pediatric eye care provider (ophthalmologist). The exam looks for uveitis. This condition is a swelling of the middle layer of the eye.

Treatment for psoriatic arthritis

Treatment will depend on your child’s symptoms, age, and health. It will also depend on how bad the condition is. The treatment team will include:

• Your child's primary healthcare provider

• A pediatric rheumatologist

• An ophthalmologist 

Treatment is done for both the skin symptoms and the joint inflammation. Some medicines used to treat psoriatic arthritis are:

• Nonsteroidal anti-inflammatory drugs (NSAIDs). These help to ease symptoms. These medicines include aspirin, ibuprofen, and naproxen.

• Immunosuppressive medicine. These are medicines that weaken the body’s immune system. These can be used to ease inflammation if NSAIDs are not working.

• Vitamins and minerals. These include calcium and vitamin D. They are used to slow bone deformities.

• Disease-modifying antirheumatic drugs (DMARDs). These medicines help prevent the arthritis from getting worse. They are most often used when more than one joint is affected. Methotrexate is the most commonly used DMARD. All DMARDs and immunosupressants increase the risk of infection.

• Immunosupressants. These medicines help weaken the immune system, which is overactive in people with this condition. They include cyclosporin and azathioprane.

• Biologic medicines. These are a newer class of DMARDs. They include adalimumab, etanercept, and infliximab. These medicines target certain parts of the immune system that lead to inflammation and joint damage.

• Corticosteroids. These are medicines that ease redness and swelling. They also increase the risk of infection.

Other treatment may include:

• Ultraviolet light treatment (UVB or PUVA)

• Heat and cold therapy

• Splints

• Exercise

• Physical therapy, to improve and keep muscle and joint function

• Occupational therapy, to help with activities of daily living

• Managing the psoriasis skin rash

• Surgery to fix or replace a damaged joint (often not needed until years after diagnosis)

Talk with your child’s healthcare provider about the risks, benefits, and possible side effects of all treatments.

Possible complications of psoriatic arthritis

Children with psoriatic arthritis are at risk of having uveitis. This is an inflammation of the eye’s middle layer. 

With early diagnosis and treatment, children can go into remission. This means that symptoms go away. But when treatment is delayed, remission is less likely. Then the condition may lead to long-term disability.

Psoriatic arthritis is also linked to an increased risk of heart disease later in life.

Living with psoriatic arthritis

Help your child manage their symptoms by sticking to the treatment plan. This includes getting enough sleep. Encourage exercise and physical therapy. Find ways to make it fun. Work with your child's school to make sure your child has help as needed. Work with other caregivers to help your child take part as much possible in school, social, and physical activities. You can also help your child find a support group, so they can be around other children with pediatric arthritis.

When to call your child’s healthcare provider

Call your child's healthcare provider if your child has any of these:

• Symptoms that don’t get better or get worse

• New symptoms