Henoch-Schonlein Purpura

Definition

Henoch-Schonlein purpura (HSP) is swelling of the blood vessels in the skin and other body organs. When it involves the skin it causes a telltale rash. The rash looks like bruising or small dots in the skin, referred to as “purpura.

People of all ages may develop HSP, but it is most common in children.

Causes

HSP is caused by an abnormal reaction of the immune system. Normally the immune system marks and attacks foreign items like viruses and bacteria. However, with HSP, the immune system attack the blood vessels. It is not clear why the immune system attacks the body.

The change in the immune system It may be triggered by:

• Bacterial or viral infections
• Certain medications
• Recent exposure to certain vaccines
• Infection by insect bites

HSP occurs most often after a respiratory infection. HSP is not contagious.

Risk Factors

HSP is most common in children aged 2 to 11 years old but can occur at any age. Factors that increase your risk of HSP include:

• Recent upper respiratory illness, such as a cold
• Recent exposure to vaccines, chemicals, cold weather, or insect bites

Symptoms

Symptoms may last for 4 to 6 weeks and may include:

• Skin rash:
  • Reddish-purple spots that are not itchy
  • Often appears on the buttocks or legs, may appear on the elbows
• Pain in the joints, especially knees and ankles
• Abdominal pain
• Blood or protein in the urine caused by kidney inflammation
• Swelling of the ankles
• Swelling of the scrotum in males
• Fever
• Blood in the stool
• Vomiting

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include:

• Blood tests
• Urinalysis
• Stool sample
• Skin biopsy from an area of the rash