Henoch-Schonlein purpura (HEN-awk SHURN-line PUR-pu-ruh) is a disorder that causes inflammation and bleeding in the small blood vessels in your skin, joints, intestines and kidneys.

The most striking feature of Henoch-Schonlein purura is a purplish rash, typically on the lower legs and buttocks. Henoch-Schonlein purpura can also cause abdominal pain and aching joints. Rarely serious kidney damage can occur.

Although Henoch-Schonlein purpura can affect anyone, it's most common in children between the ages of 2 and 6. Henoch-Schonlein purpura usually improves on its own. Medical care is generally needed if the disorder affects the kidneys.
 

Rash. The rash usually appears in all patients with HSP. The initial appearance may resemble hives, with small red spots or bumps on the lower legs, buttocks, knees, and elbows. But these change to appear more like bruises. The rash usually affects both sides of the body equally and does not turn pale on pressing.

Arthritis. Joint inflammation, involving pain and swelling, occurs in approximately three-quarters of cases, particularly affecting the knees and ankles. It usually lasts only a few days and does not cause any long-term, chronic joint problems.

Abdominal pain. In more than half of people with HSP, inflammation of the gastrointestinal tract may cause pain or cramping; it may also lead to loss of appetite, vomiting, diarrhea, and occasionally blood in the stool.

In some cases, patients may have abdominal pain before the rash appears. In rare cases, an abnormal folding of the bowel (intussusception) may cause a bowel blockage, which may require surgery to fix.

Kidney impairment. HSP can cause kidney problems, indicated by such signs as protein or blood in the urine. This is usually only discovered on urine testing, since it does not generally cause any discomfort.

In most patients, the kidney impairment is mild and goes away without any long-term damage.
 

For most people, Henoch-Schönlein purpura will get better of its own and so no specific treatment is needed. However, there are a number of things that can help with the symptoms. For example:
•Painkillers - these may help with joint pains. Paracetamol is an example. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may also be helpful. However, NSAIDs should be avoided in anyone who has suspected kidney complications or any bleeding within the gut (gastrointestinal bleeding). See separate leaflet called Anti-inflammatory Painkillers for more details.
•Rest - resting with the legs raised may help reduce the degree of rash that develops. This is because the small, round red spots (petechiae) and areas of reddish-purple skin discolouration (purpura) tend to develop in dependent areas of the body such as the legs.
•Steroid medication - this may be suggested if there are signs that the kidneys are becoming affected. Sometimes steroids are also suggested if other symptoms are severe (such as joint pains or tummy (abdominal) pain), or if boys develop scrotal pain and swelling.

In addition to this, if something is thought to have triggered Henoch-Schönlein purpura (for example, a specific medication that was being taken), this should be stopped.