Immunoglobulin A–Associated Vasculitis

(Henoch-Schönlein Purpura)

ByAlexandra Villa-Forte, MD, MPH, Cleveland Clinic
Reviewed/Revised Dec 2024
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Immunoglobulin A–associated vasculitis (formerly called Henoch-Schönlein purpura) is inflammation of mainly small blood vessels that most often occurs in children.

  • A rash of reddish purple or brown bumps and spots on the lower legs is usually the first symptom, followed by fever, joint aches, digestive upset, and kidney malfunction.

  • Biopsy of the affected skin can confirm the diagnosis.

  • For adults and children, medications that relieve pain are given as needed.

  • For adults, corticosteroids are sometimes needed to relieve joint aches and digestive upset, but, occasionally, other medications that suppress the immune system are also needed.

(See also Overview of Vasculitis.)

Immunoglobulin A–associated vasculitis (IgA vasculitis) usually affects children but can occur at any age. It may develop when the immune system responds abnormally to an infection or something else. It may be triggered by viruses that cause upper respiratory infections, medications, foods, immunizations, or insect bites. The inflammation typically occurs in blood vessels in the skin, but blood vessels in the intestine and kidney may also become inflamed.

Symptoms

A rash of small spots that look like bruises or reddish purple or brown bumps (purpura) appear on the feet, legs, and, occasionally, the trunk and arms in people with immunoglobulin A–associated vasculitis. The rash may at first look like hives that have lumped together. After a few days or weeks, new spots and bumps may appear, sometimes on the trunk too. Most children also have a fever and achy, tender, and swollen joints, including the ankles, knees, hips, wrists, and elbows.

Crampy abdominal pain and tenderness, nausea, vomiting, tarry black stools (melena), and diarrhea are common. Stools or urine may contain blood. Rarely, the intestine slides into itself, like a collapsible telescope. This complication, called intussusception, can cause sudden stomach pain and vomiting because the intestine is blocked.

Symptoms usually resolve after about 4 weeks but often return at least once after a few weeks. Most people recover completely. Rarely, chronic kidney disease develops.

In adults, intussusception is rare and chronic kidney disease is more common than in children.

Diagnosis

  • Characteristic rash in children

  • Skin biopsy

  • Urine and blood tests

Doctors suspect immunoglobulin A–associated vasculitis when the characteristic rash occurs in children.

If the diagnosis is not clear, a sample from the affected skin is taken and examined under a microscope (biopsy) to look for abnormalities in the blood vessels that can confirm the diagnosis of immunoglobulin A–associated vasculitis.

Urine tests are done to check for blood and excess protein, which indicate that the kidneys are affected. Blood tests are usually done to measure kidney function. Doctors ask people whether they have recently been ill, because immunoglobulin A–associated vasculitis may develop after a streptococcal infection.

If kidney malfunction worsens, a kidney biopsy is often done. It can help doctors determine how severe the problem is and what kind of recovery can be expected.

Treatment

  • Stopping any medication that causes the disorder

  • For adults, symptom relief and corticosteroids and possibly a medication that suppresses the immune system

  • For children, pain relief as needed

If a medication is causing immunoglobulin A–associated vasculitis, it is stopped. Otherwise, treatment is focused on relieving symptoms.

More Information

The following English-language resource may be useful. Please note that The Manual is not responsible for the content of this resource.

  1. Vasculitis Foundation: About IgA vasculitis: Provides information for people with immunoglobulin A–associated vasculitis and their caregivers, including how to find a doctor, learn about research studies, and join patient advocacy groups

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