Immunoglobulin A Vasculitis

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is a primary immune complex vasculitis affecting small vessels, characterized by IgA1-dominant immune deposits. IgAV is the most common vasculitis in childhood, and is characterized by cutaneous lesions, being palpable purpura the most frequent initial sign, followed by joint, gastrointestinal, and renal involvement. Glomerulonephritis and gastrointestinal complications are considered severe manifestations of IgAV. Regular laboratory tests are not useful in the diagnostic process. However, new serum and urine biomarkers are emerging as prognostic factors in assessing potential organ-threatening involvement. IgAV diagnosis relies on clinical criteria supported by histopathologic findings. Classification criteria have been delineated for pediatric and adult patients. Therapeutic recommendations include glucocorticoids in patients with renal, abdominal, and other organ- or life-threatening situations. Additional immunosuppressive agents may be used in patients with severe IgAV glomerulonephritis, and glucocorticoid-resistant or refractory cases. Rituximab, an anti-CD20 monoclonal antibody, has showed promising results in patients with renal involvement and refractory situations.