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Immunoglobulin A–Associated Vasculitis

(Henoch-Schönlein Purpura)


Alexandra Villa-Forte

, MD, MPH, Cleveland Clinic

Reviewed/Revised May 2022 | Modified Sep 2022
Topic Resources

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 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, drugs that relieve pain are given as needed.

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

Immunoglobulin A–associated vasculitis usually affects children but can occur at any age. It may develop when the immune system Overview of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more responds abnormally to an infection or something else. It may be triggered by viruses that cause upper respiratory infections, drugs, 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.


A rash of small spots that look like bruises or reddish purple 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 Intussusception Intussusception is a disorder in which one segment of the intestine slides into another, much like the parts of a telescope. The affected segments block the bowel and block blood flow. The cause... read more , can cause sudden stomach pain and vomiting because the intestine is blocked.

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


  • 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.


  • Stopping any drug that causes the disorder

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

  • For children, pain relief as needed

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

For adults, corticosteroids, such as prednisone, taken by mouth (orally) may help control abdominal pain and are occasionally needed to help control severe joint pain or swelling or kidney disease. If the kidneys are severely affected, people may be given the corticosteroid methylprednisolone by vein (intravenously) and then the corticosteroid prednisone and a drug that suppresses the immune system (such as mycophenolate mofetil, azathioprine, rituximab, or cyclophosphamide) by mouth.

Corticosteroids are usually not necessary for children. They may be given acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs) for pain.

More Information

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

  • Vasculitis Foundation: Provides information for patients about vasculitis, including how to find a doctor, learn about research studies, and join patient advocacy groups

Drugs Mentioned In This Article

Generic Name Select Brand Names
Deltasone, Predone, RAYOS, Sterapred, Sterapred DS
A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
CellCept, Myfortic
Azasan, Imuran
RIABNI, Rituxan, RUXIENCE, truxima
Cyclophosphamide, Cytoxan, Neosar
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
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