<unk>  <unk> , also known as IgA vasculitis, is a disease of the skin, mucous membranes, and sometimes other organs that most commonly affects children. In the skin, the disease causes palpable<unk>  (small, raised areas of bleeding underneath the skin), often with joint pain and abdominal pain. With kidney involvement, there may be a loss of small amounts of blood and protein in the urine (hematuria and proteinuria), but this usually goes unnoticed; in a small proportion of cases, the kidney involvement proceeds to chronic kidney disease.<unk>  is often preceded by an infection, such as a throat infection.<unk>  is a systemic vasculitis (inflammation of blood vessels) and is characterized by deposition of immune complexes containing the antibody immunoglobulin A (IgA); the exact cause for this phenomenon is unknown. In children, it usually resolves within several weeks and requires no treatment apart from symptom control but may relapse in a third of cases and cause irreversible kidney damage in about one in a hundred cases. In adults, the prognosis is different from in children. The average duration of cutaneous lesions is 27.9 months. For many, it tends to be relapsing–remitting over a long period of time, rather than self-limiting and there tend to be more complications.
Henoch–Schönlein purpura
Chronic testicular pain
Amyloid purpura
Testicular pain
Golfer's vasculitis
Hennekam syndrome
Roussy–Lévy syndrome
Solar purpura