Henoch-Schonlein purpura (HSP) is a disease involving inflammation and bleeding in the small blood vessels. It is more common in children than in adults, but it does not mean that adults are not susceptible to this. In most of the cases, HSP is caused by an upper respiratory infection. Other causes can be measles, chickenpox, insect bites, etc.
Symptoms include reddish-purple spots especially on legs and buttocks, sore, stiff or swollen joints, abdominal pain or bloody urine. Other rare symptoms include fever, vomiting or blood in the stool. It usually goes away in 1-3 months. In some cases, it lasts a bit longer. It is a painful disease that makes a child weak. Therefore, it is not at all advisable to send your kid to school when he is suffering from HSP. He can start going once he recovers from such a disorder.