Henoch-Schonlein Purpura (HSP)

HSP is a vasculitis a condition where small blood vessels (capillaries) in the skin, bowels, joints and kidneys become inflamed.

HSP is the most common blood vessel inflammation in children aged between 5 and 15. It is 2 times more common in boys than in girls and affects approximately 20/100,000 children per year.

• Skin rash is the leading symptom that begins with raised and red spots/patches/bumps, which in time change to a purple bruise. Classically, these spots occur over the legs/buttocks although they can appear anywhere.
  
  
• Other symptoms may occasionally precede the appearance of skin rash by a few days. They may appear simultaneously or gradually in a different order.
• Arthritis: Painful and swollen joints with limitation of movement. The joint symptoms are temporary and disappear within a few days to weeks.
• Soft tissue swelling most often occurs in the hands, feet, face and scrotum
• Abdominal pain: It is typically intermittent, and around the belly button. If there is mild to severe bloody diarrhoea, we would be concerned for an abnormal telescoping of the bowel (intussusception). This is an emergency and may need surgery.
• Kidney involvement: In some patients, there may be kidney involvement. In rare cases, kidney disease may last for months or years and may progress to kidney failure. In such cases, consultation with a kidney specialist (nephrologist) is needed.

The exact cause of HSP is unknown. Infectious agents (such as viruses and bacteria) are thought to be a potential trigger for the disease because:

• It often appears after a cold (may be due to an overly aggressive response from your child’s immune system)
• Immunoglobulin, A (IgA), a specific product of the immune system in HSP lesions is found
  

The doctor will examine your child and make a diagnosis based on your child’s signs and symptoms.

What laboratory and other tests are useful?

• Urine analysis is performed during the disease to detect kidney involvement. Microscopic blood in urine is common and resolves with time.
• Kidney biopsy is performed only for significant kidney disease.
• Ultrasound may be recommended to rule out other causes of abdominal pain and to check for possible complications, such as intussusception.
  

Most HSP patients do not require any specific treatment.

• Steroids are indicated for patients with severe skin rash, hand/foot swelling and bowel symptoms.
• Steroid sparing drugs are used very rarely, only for severe kidney involvement or recurrent disease.

How long will the disease last?
The entire course of the disease is about 4 to 6 weeks. Half of the children with HSP have at least one recurrence within a 6-week period. Most patients recover completely. New infections may trigger a recurrence of the HSP.

What kinds of periodic check-ups are necessary?
Your doctors may ask for repeat urine tests and blood pressure measurement, and will advise on the frequency of check-ups and urine test.

How to collect the clean midstream urine sample?

• Hydrate prior to urine collection.
• If menses has already occurred, the ideal collection date is 2 weeks after the first day of the last period.
• Clean genital area with soap and water and dry well.
• Female: Dry from front to back
• Male: Retract the foreskin if present and clean the head of the penis thoroughly.
• Pass a little urine into the toilet. Then, hold the specimen container to ‘clean catch’ urine sample.
  

What about activities?
There are no limitations. Patients with HSP can continue normal physical activity as long as they are not in pain.

When to contact your doctor?
Contact your doctor when your child has:

• New swelling in hands, feet or scrotum
• Visible blood in the urine or stool
• Severe abdominal pain (seek medical attention at emergency department immediately)