Immunoglobulin A vasculitis, formerly called Henoch-Schönlein purpura (HSP), is the most common systemic vasculitis in childhood. It is a small-vessel vasculitis mediated by type III hypersensitivity, manifested as rash accompanied by gastrointestinal (GI) symptoms, arthritis, and nephritis. The etiology of this disease (a leukocytoclastic vasculitis) is still uncertain, but immune complexes of IgA and unidentified antigens seem to have a central pathogenic role. Most often the diagnosis is established after the clinical examination; it is easy at first glance when the clinical presentation includes the classic tetrad of rash (nonthrombocytopenic palpable purpura), arthralgia/arthritis, abdominal pain, and renal manifestations but may be difficult when the gastrointestinal manifestations precede the skin purpuric rash. Gastrointestinal involvement is frequently seen and varies from mild symptoms to severe complications; sometimes the gastrointestinal symptoms (colicky abdominal pain, nausea, vomiting, diarrhea, gastrointestinal bleeding) are the first manifestations of the disease. Immunoglobulin A vasculitis is usually a self-limited disease with a benign course, and the treatment is often symptomatic; in severe cases corticosteroids are necessary.
Part of the book: Digestive System