Polyarteritis nodosa

This page explains about polyarteritis nodosa (PAN), what causes it and how it can be treated. It also gives details of what to expect when a child comes to Great Ormond Street Hospital (GOSH) for assessment and treatment.

Polyarteritis nodosa (shortened to PAN) is a rare form of vasculitis in which the medium and/or smaller sized arteries become damaged and inflamed. It can sometimes be triggered by an infection, particularly if this infection was with a bug called streptococcus but we are unsure of the exact cause.

As with most types of vasculitis, it is diagnosed by the signs and symptoms that indicate inflammation and when doctors have ruled out other diseases that can have these symptoms. A blood test will be necessary and often a skin biopsy. Other biopsies may also be needed to check the extent of any damage to organs like the liver or kidneys. A specific test called an arteriogram (an x-ray test of the arteries) can show up changes in the arteries.

• General health
  A persistent unexplained fever or temperature with a general feeling of being unwell
• Skin
  Several types of skin rashes or palpable (able to be felt) lumps due to inflammation in the skin
• Digestive system
  Tummy aches and weight loss
• Kidneys
  Protein is often found in the urine which indicates that there is inflammation in the kidneys, and sometimes the blood pressure may be too high
• Other organs: heart, lungs, brain, nerves and liver
  Can be affected and damaged depending on which arteries are inflamed

It is treated with steroids to reduce the inflammation in the body and a disease modifying drug such as cyclophosphamide, azathioprine, mycophenolate mofetil, or methotrexate. The doctor will decide which of these is most appropriate for the child. More information about these medicines is available in our general vasculitis information sheet.

There is a range of possible outcomes depending on the severity of the disease and how much damage is already there in vital organs such as the kidneys. Early diagnosis and prompt treatment improves the outcome, but despite this PAN can be a serious disease with a small risk of death, particularly if diagnosis is delayed. Many children will respond well to the medicines and not have further relapses. Others will have a more chronic, relapsing course and require long-term maintenance on medications.

Overall, most children require treatment for two to three years, after which treatment can be withdrawn usually without return of the disease. The child's doctor may invite them to join a long-term follow-up study looking for early hardening of the arteries.