According to the Arthritis Foundation, 30 percent of people with psoriasis will also develop psoriatic arthritis (PsA). PsA is an autoimmune disease where the body attacks healthy tissues in the skin and joints, causing areas of painful inflammation. PsA may lead to joint and tissue damage if not treated promptly.
PsA is a chronic condition that gets worse over time. However, there are often periods where people may experience few, if any, symptoms of the disease. PsA may affect joints on one or both sides of the person's body.
Similar to psoriasis, PsA may present differently from person to person. Appearance will depend on the following factors:
- the symptoms a patient experiences
- how advanced the disease is
- differences between individuals
Individuals with early or less severe cases of PsA may show very minor symptoms when looked at with the naked eye.
Even under imaging, to the untrained eye, the earlier stages of PsA may not look very pronounced.
People with psoriasis have the biggest risk of later developing PsA.
Some of the symptoms of psoriasis, such as skin and nail changes, will be the same for PsA.
PsA can cause painful, "sausage-like" swelling in the fingers and toes.
This may occur before the person experiences any symptoms in their joints.
People with more advanced stages of PsA may develop mutations to the fingers and fingernails.
Severe or advanced PsA may also cause mutations to the joints, particularly in the hands and feet.
When imaging is used, people with similar, more advanced stages of PsA may look like this. In this image, the joint pain is indicated in red.
Along with joint pain, swelling, and a general feeling of warmth, PsA also causes additional symptoms.
Some additional symptoms include:
- Lower back pain. PsA may cause people to develop spondylitis, a condition that causes inflammation of the joints between the bones of the spine, in the joints between the spine, and in the pelvis.
- Swollen fingers and toes. PsA could cause a painful swelling that makes the fingers and toes resemble sausages. A person may also develop swelling and deformities in their feet and hands before experiencing significant joint symptoms.
- Foot pain. PsA can also cause pain at the connection points where ligaments and tendons attach to the bones. This is particularly common towards the back of the heel or in the sole of the foot.
- Swollen joints. Large joint swelling is a prevalent symptom of PsA. In particular, it affects the lower joints.
There are several factors that can increase the chances that a person may develop PsA.
Some of these factors include:
- Personal diagnosis of psoriasis. People who have psoriasis have the biggest risk of developing PsA. People with psoriasis lesions on the nails are even more likely to develop PsA.
- Family history. People who do not have psoriasis, but have a family member with psoriasis have a strong likelihood of developing PsA.
- Age. People between the ages of 30 and 50 are far more likely to develop PsA. Still, it is possible to develop at any age.
A doctor will look for swelling, skin and nail changes, and painful joints if they suspect someone has PsA.
People with psoriasis should speak with their doctor about the possibility of developing PsA, especially where the lesions appear on the hands.
Additionally, anyone with a family history of psoriasis should talk to their doctor at the first sign of joint pain.
Early detection and treatment is a key to successful treatment.
Doctors will check for the following to diagnose PsA:
- swollen and painful joints
- skin and nail changes typical of psoriasis
- certain patterns of arthritis typical of PsA
A doctor may use X-ray images to look for joint damage. If X-rays are not detailed enough or cannot be used, a doctor may order an MRI, ultrasound, or CT scan to look for more details in the affected joints.
A doctor may order blood tests in order to rule out other types of arthritis that have similar signs and symptoms. People with PsA may show higher levels of inflammation and mild anemia from their blood tests but otherwise the results may be normal.
In cases where psoriasis is not confirmed, a doctor may order a skin biopsy to confirm psoriasis is present prior to diagnosing PsA.
Treatment for PsA varies based on the person's level of pain, swelling, and stiffness of their joints, fingers, or back.
People with mild cases of PsA may only require treatment when their joints are painful and may be able to stop therapy when their joints feel better. At first, a doctor may try non-steroidal, anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen.
In some cases, a doctor may prescribe disease-modifying anti-rheumatic drugs (DMARDs) that slow the progression of the arthritis and help save the joints and ligaments from permanent damage. In some cases, these drugs may be used in combination with others.
The antimalarial drug hydroxychloroquine may help, but doctors often avoid it because it may cause psoriasis to flare. A doctor may also prescribe azathioprine for patients with severe forms of psoriatic arthritis.
In addition, there are several biologic type medications available that a doctor may prescribe in order to treat PsA. These are taken by injection or by mouth and include:
There are a number of medications available to help manage the pain and swelling caused by PsA.
- Ustekinumab is a biologic injection that a doctor gives in their office that treats both PsA and psoriasis.
- TNF inhibitors include adalimumab, etanercept, golimumab, certolizumab, and infliximab. TNF inhibitors may help both the arthritis and psoriasis.
- Secukinumab is a newer type of biologic injection approved to treat PsA and may also be helpful in treating psoriasis.
- Corticosteroid injections may help with swollen joints.
A final method of treatment may include surgery. Surgery can help repair or replace badly damaged joints, particularly in the hands or feet.
PsA is a degenerative disease. Over time, a person may experience worsening symptoms, permanent joint damage, and possible deformities to their toes, fingers, and limbs.
Early diagnosis and treatment may slow down the progression of the disease and help reduce permanent damage to the joints.