IgAvaskulitt

IgA-vaskulitt, or IgA-vasculitt, is a small-vessel vasculitis characterized by deposition of IgA-containing immune complexes in the walls of small vessels. It most commonly affects children but can occur at any age. The disease often follows an upper respiratory or other infection and involves multiple organ systems, most notably the skin, joints, abdomen, and kidneys.

The pathophysiology involves IgA antibodies, particularly IgA1, forming immune complexes that deposit in vessel walls and trigger inflammation (leukocytoclastic vasculitis). The exact trigger is not always identified, but infections are a common antecedent. This immune-mediated process can lead to vascular leakage and inflammation in the skin, joints, gut, and kidneys.

Clinically, the hallmark is palpable purpura, usually on the lower limbs and buttocks. Joint symptoms include periarticular pain and swelling, most often in the ankles and knees. Abdominal symptoms can range from mild pain to severe cramping and, rarely, intestinal bleeding or perforation. Renal involvement occurs in a significant minority and may present as hematuria and proteinuria; in some cases it progresses to nephritis. Adults tend to have a higher risk of renal involvement than children.

Diagnosis is primarily clinical but is supported by laboratory tests and, when needed, a skin or sometimes kidney biopsy. Laboratory findings may show normal platelet counts with elevated inflammatory markers; urinalysis is important to detect blood and protein in the urine. Immunofluorescence of a skin biopsy typically shows IgA deposition in vessel walls.

Treatment is usually supportive, emphasizing hydration, rest, and pain control. Most cases resolve over weeks to months. Corticosteroids may be used for severe abdominal symptoms or significant renal involvement; more aggressive immunosuppressive therapy is reserved for severe or progressive kidney disease. The prognosis is generally favorable in children, with most recovering fully, while adults have a higher risk of persistent kidney problems. Regular follow-up with renal function monitoring is recommended.