musculoskeletal and connective tissue disorders
Immunoglobulin A–Associated Vasculitis (IgAV)
Diagnosis of IgAV
Biopsy of skin lesions with direct immunofluorescence The 2012 Chapel Hill Consensus Conference ( Diagnosis reference ) defined immunoglobulin A–associated vasculitis (IgAV) as vasculitis with IgA1-dominant immune deposits, affecting small vessels in the skin and gastrointestinal tract and frequently causing arthritis. IgAV is also associated with glomerulonephritis indistinguishable from IgA nephropathy. The diagnosis of IgAV is suspected in patients, particularly children, with typical skin findings. It is confirmed by biopsy of skin lesions when leukocytoclastic vasculitis with IgA in the vessel walls is identified by immunofluorescence. Biopsy is unnecessary if clinical diagnosis is clear in children. Urinalysis is done; hematuria, proteinuria, and red blood cell casts indicate renal involvement. Complete blood count and renal function tests are done. If renal function is deteriorating, renal biopsy may help define the prognosis. Diffuse glomerular involvement or crescent formation in most glomeruli predicts progressive renal failure. 1.Jennette JC, Falk RJ, Bacon PA, et al: 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides.Arthritis Rheum65(1):1-11, 2013. doi: 10.1002/art.37715 