A 20 year old girl presents with abdominal pain, ahralgia and a palpable purpuric rash all over the body. The most likely diagnosis is:

Answer is A (Henoch Schonlein Purpura): Palpable Purpura (most commonly distributed over the buttocks and lower extremities), ahralgias, and abdominal pain are all charachteristic features of Henoch-Schonlein purpura. Although H.S purpura is usually seen in children and most patients range in age from 4-7 years, Harrisons text clearly mentions that this condition may also be seen in infants and adults. The charachteristic clinical manifestation of palpable purpura, ahralgia and abdominal pain in this young adult suggest the diagnosis of H-S purpura.