Henoch-Schonlein purpura

Symptoms of Henoch-Schonlein purpura include:

• Rash. The main symptom is a rash made up of raised spots called purpura. Patches of the rash can look like bruises. The color of this rash may be shades of red or purple depending on skin color. The rash typically forms on the legs and feet. It also can appear on the buttocks, arms, face, chest, back and belly. The rash may be worse in areas where clothing puts pressure on the skin, such as the sock line and waistline.
• Swollen, sore joints. People with Henoch-Schonlein purpura often have pain and swelling around the joints. The swelling typically is in the knees and ankles. Sometimes, joint pain develops about 1 to 2 weeks before the rash appears. Joint soreness and swelling typically go away without any lasting damage when the illness passes.
• Digestive tract symptoms. Many people with Henoch-Schonlein purpura develop belly pain, nausea and vomiting. They also may have black, tarry or bloody stools. These symptoms sometimes happen before the rash appears.
• Kidney involvement. Henoch-Schonlein purpura can affect the kidneys. This typically doesn't cause any noticeable symptoms. But a urine test may show protein or blood in the urine when kidneys are affected. Usually this goes away once the illness passes. Rarely, some people develop kidney disease that lasts a long time.

See your healthcare professional if you have a rash you think may be Henoch-Schonlein purpura, and you also have serious belly pain, nausea, vomiting or bloody stools.

If your child develops a rash that you think may be Henoch-Schonlein purpura, make an appointment for your child to see a healthcare professional as soon as possible.

In Henoch-Schonlein purpura, some of the body's small blood vessels become inflamed. That can cause bleeding in the skin, belly and kidneys. It's not clear why the inflammation develops. It may be the result of an immune system response in the body.

Many people who have Henoch-Schonlein purpura develop it after an upper respiratory illness, such as a cold.

Other possible triggers of Henoch-Schonlein purpura include strep throat, COVID-19 and other infections. Insect bites and cold weather, as well as some medicines and foods, also may trigger Henoch-Schonlein purpura.

Factors that raise the risk of developing Henoch-Schonlein purpura include:

• Age. The disease mainly affects children and young adults. Most cases happen in children between the ages of 3 and 10.
• Sex assigned at birth. Henoch-Schonlein purpura is slightly more common in males.
• Family history. Henoch-Schonlein purpura sometimes runs in families. So it's possible that genetics may play a role in who gets this illness.
• Race. White and Asian people are more likely to develop Henoch-Schonlein purpura than are other people.

For most people, symptoms of Henoch-Schonlein purpura go away within a month without any lasting problems. But it is common for people who've had this illness to get it again within 4 to 6 months. If Henoch-Schonlein purpura comes back, symptoms often are milder than before.

Other health concerns that can happen due to Henoch-Schonlein purpura, called complications, include:

• Kidney damage. The most serious health issue linked to Henoch-Schonlein purpura is kidney damage. This risk is greater in adults than in children. Sometimes the damage is serious enough that dialysis or a kidney transplant is needed.
• Bowel blockage. Henoch-Schonlein purpura can cause a section of the bowel to fold into itself like a telescope. This is a condition called intussusception. It prevents anything from moving through the bowel. The risk is greater in children than in adults.