IgA vasculitis (Henoch-Schönlein purpura)

What is IgA vasculitis?

IgA vasculitis (previously known as Henoch-Schönlein purpura or HSP) is most common in children between the ages of two and 10 but can occur throughout childhood and adolescence. In this condition, there is an immune response (usually to an unknown trigger) that leads to vasculitis, or inflammation of small blood vessels. The most common affected areas in the body are in the skin, joints, kidneys and bowel.

Signs and symptoms of IgA vasculitis

Children with IgA vasculitis always have a rash consisting of pink, red or purple blood-filled spots that do not fade when pressed. The spots are often raised but can be flat and can vary in size. The rash is often described as petechiae or purpura. It usually appears on both lower legs but can appear on the upper legs, buttocks and even the face, trunk and arms. The rash can often be worse around the joints, such as the ankles or knees, or in areas where clothes can apply pressure, such as the sock line and waistline.

The signs and symptoms may also include:

• abdominal pain (mild or severe), nausea and vomiting and sometimes blood in the stool
• joint pain and joint swelling
• blood or protein in the urine

Causes of IgA vasculitis

We do not know exactly what causes IgA vasculitis, but it often occurs after a child has had a viral infection.

Diagnosis of IgA vasculitis

Children who have the typical rash of IgA vasculitis can often be easily diagnosed. Seventy-five per cent of children develop a typical rash first. Blood tests are done to ensure that there is no other reason for petechiae or purpura, such as low platelets or abnormal coagulation, both of which could lead to bleeding in small vessels of the skin. A diagnosis of IgA vasculitis can be made in children with the rash and normal blood tests if they also have at least two of the following:

• abdominal pain (seen in up to 50 per cent of children)
• joint pain or joint swelling (seen in 50 per cent to 75 per cent of children)
• kidney involvement (blood or protein in the urine; seen in up to 50 per cent of children)

Children who have one or more symptoms without a classic rash may require repeat assessments to monitor for the rash and further investigations to make the diagnosis or exclude other diagnoses.

What your child's health-care provider can do for your child with IgA vasculitis

Your child's health-care provider will physically examine your child in order to make a diagnosis. The health-care provider may order blood and urine tests.

Treatment of most symptoms includes pain control using acetaminophen, ibuprofen or naproxen at home. Children with severe abdominal pain or vomiting may need admission to hospital for IV fluids or steroids, which have been shown to help reduce the duration of abdominal symptoms. Children with severe abdominal symptoms may also need to be closely monitored for complications that require assessment by a surgeon.

Possible complications of IgA vasculitis

Kidney problems

About 50 per cent of children with IgA vasculitis develop problems with their kidneys. Most of these are mild and temporary. Only a small minority will have serious kidney disease. Kidney involvement usually develops within six months of the rash, so most children should be monitored regularly with urine tests and blood pressure monitoring for the first six months to one year after diagnosis, then annually as part of their periodic health examination.

Intussusception

Intussusception is another rare but serious complication of IgA vasculitis. In up to 5 per cent of children, the inflammation and swelling in the small bowel can lead to an obstruction that can be diagnosed on ultrasound. A child with intussusception may need surgery to relieve the obstruction.

Recovery

IgA vasculitis is considered a one-time illness, though children occasionally get it more than once. Up to one-third of children may have recurrent symptoms within a few months of diagnosis. Most children recover completely from this illness with no long-term side effects.

For most children who experienced kidney inflammation, the kidneys return to normal in a few days. In some cases, however, the kidneys can remain inflamed for as long as two years.

What you can do to help your child with IgA vasculitis

There is no specific treatment for IgA vasculitis. You can support your child by trying to make them comfortable and treating pain. The medications used will depend on your child’s symptoms. Your child’s health-care provider will advise you on the best treatment for them.

When to see a health-care provider

The rash of IgA vasculitis can look similar to other very serious conditions that require immediate treatment. If your child develops a rash that looks like the rash of IgA vasculitis, seek immediate medical assistance.