Arthritis that develops in children is known as juvenile idiopathic arthritis. There are six different subtypes of juvenile idiopathic arthritis, which includes a subtype known as juvenile psoriatic arthritis. As the name suggests, this subtype develops in children who have psoriasis, a skin disease characterized by the development of red, scaly rashes. About one third of all children who have psoriasis will develop juvenile idiopathic arthritis.
In approximately 50 percent of children with juvenile psoriatic arthritis, symptoms of arthritis begin before the manifestation of psoriasis while in the remaining 50 percent, symptoms of psoriasis precede arthritis. Juvenile psoriatic arthritis develops in both boys and girls and can occur at any age. Generally, the disease only affects a few joints, particularly joints located in the hips, back, finger and toes.
Juvenile psoriatic arthritis: Causes
It is not currently known what causes the development of juvenile psoriatic arthritis. However, researchers do know that this disease results from immune system malfunctioning, and therefore, is an autoimmune disease. The immune system plays an important role in protecting us and our bodies from pathogens by attacking substances that they recognize as foreign and not belonging in the body. However, in the case of autoimmune disease, the immune system becomes confused and starts to identify the body’s own healthy tissue as foreign. Inflammation is a key mark of autoimmune diseases and therefore, patients with arthritis will have joint inflammation and swelling.
Though we know that juvenile psoriatic arthritis is an autoimmune disease, it is not clear what triggers this malfunctioning of the immune system. Studies point to a role for both genetics and environmental factors in the triggering of the immune system. Environmental triggers that lead to the development of psoriasis include stress, skin injury, certain medicines, infections, diet, allergies and weather.
Symptoms of juvenile psoriatic arthritis
While the joints affected and the severity of the symptoms varies from individual to individual, certain symptoms are common across patients. Patients with juvenile psoriatic arthritis may experience these symptoms:
- Inflammation, stiffness, pain and swelling of joints
- Extreme swelling of joints in the fingers or toes, may look “sausage-like”
- Stiffness of joints is particularly severe in the morning
- Depressions in the surface of the nail (a condition called pitted nails)
- Fatigue or weakness
- Inflammation of the eye (a disease called uveitis)
- Decreased range of movement of joints
- Skin rash that appears red on the trunk, joints, face or scalp. Sometimes, the rash can be itchy.
Diagnosis: How will your doctor know if your child has juvenile psoriatic arthritis?
If your child’s doctor suspects that he or she has juvenile psoriatic arthritis, they will refer you to a specialist known as a rheumatologist. Unfortunately, there is no single test that can prove the presence of juvenile psoriatic arthritis and so the rheumatologist will make a diagnosis based on a variety of different things.
The rheumatologist will ask detailed questions about the symptoms such as when they started, exactly what they are, how long they last for, and others. The rheumatologist will also discuss your personal and family medical history and then conduct a full physical examination. The rheumatologist may also order tests for further evidence that would indicate the patient has juvenile psoriatic arthritis. These tests include:
- Blood tests, to look markers of inflammation and presence of certain antibodies that are highly elevated in autoimmune disease. This test can tell the doctor that the patient likely has an autoimmune disease.
- Imaging tests, such as X-rays or MRIs, which can help visualize damage to the joints.
- Urine test, as a substance called uric acid is elevated in the urine of children with this disease
- Eye exam, as children with juvenile psoriatic arthritis are more likely to develop inflammation of the eye.
Treatment: How is juvenile psoriatic arthritis managed?
As there are no treatments that can cure juvenile psoriatic arthritis, doctors will administer therapies to help relieve symptoms. Medications to help ease symptoms include:
- Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, reduce inflammation and pain.
- Biologic therapy, drugs that target the immune system and help relieve inflammation. For example, TNF-inhibitors are a type of biologic therapy that suppress the activities of TNF-alpha, which is a pro-inflammatory molecule.
- Disease-modifying antirheumatic drugs (DMARDs) suppress the immune system and alleviate symptoms.
However, biologic therapy and DMARDs are still under investigation and therefore, are not approved for treatment of juvenile psoriatic arthritis. Other non-medical treatments for juvenile psoriatic arthritis include:
- Physical therapy. Patients can work with a physical therapist to learn strategies to move and exercise that can help them keep their range of motion.
- Exercise. Conducting exercise regularly can help children with this disease stay flexible and increase strength of their joints.
- Occupational therapy. Working with an occupational therapist can help children perform everyday tasks.
- Hydrotherapy. This type of therapy involves using a warm pool for conducting exercise and has been shown to help strength joints and increase flexibility.