Henoch-Schönlein purpura (say "hen-awk shern-line purr-purr-ah") is a disease that causes the blood vessels in the skin to become inflamed (irritated and swollen). This inflammation is called vasculitis. When the blood vessels in the skin are inflamed, they can bleed, causing a rash that is called purpura. HSP also can affect blood vessels in the bowel and the kidneys. When this happens, the intestines and the kidneys may also bleed.
HSP causes a skin rash that looks like small bruises or small reddish-purple spots on the buttocks, around the elbows and on the legs. HSP can also cause pain in the joints (such as knees and ankles), stomach pain, nausea, vomiting and diarrhea. The symptoms usually last for about 4 to 6 weeks. If the blood vessels in the bowel and the kidneys get inflamed, HSP can make you bleed when you have a bowel movement or when you urinate. Serious kidney problems don't happen very often, but they can occur. If you or your child has symptoms of HSP, see your doctor. In rare cases, an abnormal folding of the bowel called intussusception (say "in-tuh-suh-sep-shun") can occur. This makes a blockage in the intestines that may need surgery.
The exact cause of HSP is unknown. Doctors think HSP happens when a person's immune system doesn't fight an infection like it's supposed to. It might be triggered by bacterial or viral infections, medicines, insect bites, vaccinations or exposure to chemicals or cold weather. You may catch an infection that caused someone's immune system to respond with HSP, but HSP itself isn't contagious. Doctors don't know how to prevent HSP yet.
HSP is more common in boys than in girls. It most commonly affects children 2 years to 11 years of age, but it may affect people of any age.
There is no specific treatment for HSP. Medicines can help you feel better and treat an infection that may have triggered HSP. Fortunately, HSP usually gets better without any treatment. Anti-inflammatory medicines, such as ibuprofen (some brand names: Advil, Motrin) or naproxen (brand name: Aleve), can help the pain in your joints. Sometimes medicines like prednisone can help people who have severe joint and stomach pain.
Usually, HSP doesn't cause lasting problems and gets better on its own. About half of the people who have had HSP once will get it again. A few people will have kidney damage because of HSP. Your doctor may want to check urine samples several times after HSP goes away to check for kidney problems. Be sure to see your doctor regularly during this time.
Written by familydoctor.org editorial staff