Henoch-Schonlein purpura (HSP) is a form of vasculitis or inflammation of the blood vessels. HSP affects the capillaries in the skin causing bleeding which appears as a purplish rash most commonly on the buttocks and lower legs. Sometimes joint pain or abdominal pain accompanies it and HSP commonly affects the kidneys.
Henoch-Schonlein purpura most often occurs in the spring after the person has had a bacterial or viral upper respiratory infection. It is thought that HSP is the result of an immune reaction after the illness though drugs or certain vaccinations can also trigger a HSP response.
Henoch-Schonlein purpura occurs most commonly in children and young adults. Medicine.net says that it is a mild illness that generally resolves on its own in about a month unless there are kidney or bowel complications requiring further treatment.
According to Mayoclinic.com, there are four main characteristics of Henoch-Schonlein purpura though not everyone develops all four symptoms:
• A rash (purpura) appears which look like red/purple bruises and is the “universal” sign that someone has Henoch-Schonlein purpura. The main site is the buttocks and legs and feet but can appear on the arms, face or trunk.
• Painful or swollen joints, particularly of the knees and ankles, may develop one to two days before a rash appears. Joint symptoms usually clear after recovery from HSP.
• Gastrointestinal symptoms such as abdominal pain, nausea, vomiting and bloody diarrhea may develop. GI symptoms occur in over 50 percent of children with HSP. In rare cases, a bowel obstruction can occur.
• Kidney involvement occurs in roughly 20 to 50 percent of those with HSP. Blood and or protein in the urine may be found with urine testing that is not apparent to the eye.
Kidney symptoms usually resolve after recovery from HSP but in some cases further kidney disease may develop. In some cases HSP damages the kidney and the person develops end stage renal failure requiring dialysis or a kidney transplant. Adults are at greater risk than children.