Ans. is 'a' i.e., Henoch-Schonlein purpura Henoch-Schonlein purpura* Henoch-Schonlein purpura, also referred to as anaphylactoid purpura, is a small-vessel vasculitis characterized by palpable purpura (most commonly distributed over the buttocks and lower extremities), arthralgias, gastrointestinal signs and symptoms, and glomerulonephritis.Clinical features* It is seen pediatric patients having palpable purpura.* Most patients develop polyarthralgias in the absence of frank arthritis.* Gastrointestinal involvement is seen in almost 70% of pediatric patients. It is characterized by colicky abdominal pain usually associated with nausea, vomiting, diarrhea, or constipation and is frequently accompanied by the passage of blood and mucus per rectum; bowel intussusception may occur.* Renal involvement occurs in 10-50% of patients and is usually characterized by mild glomerulonephritis leading to proteinuria and microscopic hematuria, with red blood cell casts in the majority of patients; it usually resolves spontaneously without therapy. Rarely, a progressive glomerulonephritis will develop.