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About your disease

Psoriatic arthritis (PsA) is a type of inflammatory arthritis that usually appears in people with a skin disease called psoriasis.

PSORIASIS
Psoriasis is an autoimmune disease that occurs when the immune system mistakenly “attacks” the skin. The result is red (inflamed) patches of skin, which are covered with silvery-white scales. Severity of psoriasis varies with each person and can range from a few isolated patches on the knees and elbows (mild) to widespread patches that cover large areas of skin (severe).

In PsA, the joints are also targeted by the immune attack. The result is swelling, pain and warmth (inflammation) in the joints. Generally, PsA starts after the onset of psoriasis. However, having psoriasis does not mean you will have PsA. In fact, most people with psoriasis will never develop PsA.

Types of PsA

Scientists have discovered five types of PsA:

  • Asymmetric pattern: One of the mildest forms, PsA affects one to three joints on different sides of the body.
  • Symmetric pattern: Involves many more joints and looks very much like rheumatoid arthritis (RA).
  • Distal pattern: Involves the end joints of the fingers closest to the nails. 
  • Spinal pattern: Involves the joints of the spine and the sacroiliac joints linking the spine to the pelvis.
  • Destructive pattern: Affecting only a few people, is a severe, painful, deforming type of arthritis.

PsA CAN ALSO CAUSE INFLAMMATION IN TENDONS AROUND THE JOINTS.

This is called “enthesitis”. Some of the common spots for this are the back of the heels, underneath the bottoms of the feet, and on the outside of the hips. In other people, PsA can cause the fingers or toes to swell up like sausages. This is called “dactylitis”.

Symptoms

Both PsA and psoriasis are chronic diseases, but you may have periods when your symptoms improve or go into remission alternating with times when symptoms are worse.

PsA can affect joints on just one side or on both sides of your body. 

  • The signs and symptoms of PsA often resemble those of RA.
  • Both RA and PsA cause joints to become painful, swollen, and warm to the touch.

PsA may also cause:

  • Swollen fingers and toes
    Painful, sausage-like swelling of your fingers and toes as well as swelling and deformities in your hands and feet before having significant joint symptoms
  • Foot pain
    Pain at the points where tendons and ligaments attach to your bones, especially at the back of your heel (Achilles tendonitis) or in the sole of your foot
  • Lower back pain
    Spondylitis, which causes inflammation of the joints between the vertebrae of your spine and in the joints between your spine and pelvis, may occur in some people with PsA.
  • Morning stiffness
    Morning stiffness and tiredness can occur in patients with PsA.

Diagnosis

There is no single diagnostic test for PsA.

If you have psoriasis along with red, swollen fingers or toes, and nails and skin are affected along with the joints, a diagnosis of PsA is likely.

Since the symptoms of PsA can be similar to other forms of inflammatory arthritis, your doctor will:

  • Perform a physical examination
  • Order blood work
  • Request X-rays to help confirm the diagnosis

Other health problems that may occur with PsA

NAIL/HAND CONDITIONS/PROBLEMS

Nail changes can occur with PsA. The nail may separate from the nail bed and/or become pitted, mimicking fungal infections. 

Nails

EYE CONDITIONS/PROBLEMS

Redness and pain of the eye may also occur in patients with PsA.