Psoriatic arthritis and the skin: joint symptoms, nails and treatment

Psoriasis is a skin condition that causes patches of red, flaky skin covered with silvery scales. The NHS says some people with psoriasis will get psoriatic arthritis as they get older. Arthritis UK explains that psoriatic arthritis can cause pain, swelling and stiffness in and around the joints, and affects about 1 in 4 people who already have psoriasis. Some people may develop it before the psoriasis is present, and in rare cases people have psoriatic arthritis and never have noticeable skin patches.

Both are autoimmune conditions, caused by a fault in the immune system. Arthritis UK describes psoriatic arthritis as a type of spondylarthritis, a group of conditions with similar symptoms.

The NHS lists the main symptoms, and Arthritis UK adds more detail. People often have two or more, and they range from mild to severe.

• Pain, swelling and stiffness in one or more joints, often worse in the morning or after rest.

• Swollen fingers or toes, known as dactylitis or sausage digit, where the whole finger or toe swells.

• Nail changes: tiny dents or pits, colour change, thickening, and nails lifting away from the nail bed.

• Enthesitis: pain where tendons and ligaments attach to bone, commonly at the back of the heel or sole of the foot, which can make standing or walking difficult.

• Severe, persistent tiredness (fatigue) that does not improve with rest.

The NHS says to see a GP if you have joint pain, stiffness and swelling that keeps coming back, even if you do not have psoriasis, because these symptoms need to be checked. If you already have psoriasis and your treatment is not working or has side effects, you should also see a GP. The NHS notes that other conditions can cause similar symptoms, including osteoarthritis, rheumatoid arthritis and gout.

Arthritis UK says to seek urgent medical attention if one or both eyes are red and painful, particularly with a change in vision, as this may be a complication of the condition. You could go to your GP, an eye hospital or your local A&E department.

The NHS says that if the GP thinks you may have psoriatic arthritis, they will refer you to a specialist (rheumatologist). Tests you may have include blood tests, a joint fluid test where fluid is removed from an affected joint and tested, and X-rays, ultrasound scans and MRI scans. There is no single test, and the specialist looks at the pattern of joint, nail and skin changes together.

The NHS says medicines are the main treatment, and that if a medicine does not help your symptoms you should tell your doctor, as another may work better.

The NHS notes that some people may also get symptoms of psoriasis, such as dry scaly skin, at the same time as joint symptoms. Pits and nail lifting are listed among the symptoms of psoriatic arthritis by both the NHS and Arthritis UK. If you have nail psoriasis, tell the clinician who looks after your skin about any joint symptoms, and tell your rheumatology team about skin changes, so that treatment can cover both.

The NHS suggests exercising regularly, with low impact options such as swimming, walking and yoga, losing weight if overweight to reduce pressure on joints, cutting down on alcohol if you take medicines, and not smoking. Arthritis UK says the effects vary a great deal between people, that it can cause long-term damage to joints, bones and other tissue, especially if untreated, and that starting the right treatment as soon as possible gives the best chance of living a full and active life.

On the NHS the pathway is GP, rheumatology, then monitoring by specialist teams, with dermatology where skin disease is significant. Private rheumatology and dermatology appointments can be quicker, but the same classes of medicines are used, and long-term monitoring often continues in NHS clinics. Ask who coordinates skin and joint treatment so that one team is aware of what the other prescribes.