You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Frequency of renal involvement in HSP - and explain in detail?
Henoch-Schonlein purpura(HSP) is an acute, systemic, immune complex-mediated, leukocytoclastic vasculitis. It is characterized by a triad of palpable purpura (without thrombocytopenia), abdominal pain, and ahritis. Most patients have an antecedent upper respiratory illness. More than 90 percent of Henoch-Schonlein purpura cases occur in children younger than 10 years; however, adults with this condition are more likely to experience complications than children. All patients with Henoch-Schonlein purpura develop a purpuric rash, 75 percent develop ahritis, 60 to 65 percent develop abdominal pain, and 40 to 50 percent develop renal disease. www.aafp.org