Nickan Research Institute Immunopathologia Persa 2423-8015 2 2 2016 07 01 IgA vasculitis; from definition to classification of morphologic variables; an updated mini-review e17 EN Hamid Nasri Journal Article 2015 10 27 2015 12 12 All inflammatory modifications in the vessel wall are described as vasculitis. Pediatric vasculitis may existing with various clinical presentations. Immunoglobulin A vasculitis, is an immune complex vasculitis affecting small vessels with dominant IgA deposits. It is a small vessel vasculitis which can engage kidneys, gut, joints and skin, to varying degrees. Immunoglobulin A vasculitis, is the most common pediatric vasculitis usually recovers spontaneously, however, it is necessary to closely follow up of this disease because of the risk of kidney involvement, particularly in late-onset adult form of the disease. Both IgA nephropathy and IgA vasculitis are the same diseases, while IgA vasculitis is the systemic form of IgA nephropathy with presence of small vessel vasculitis. We suggest application of Oxford classification for IgA vasculitis and including of crescent as an additional morphologic variable in addition to MEST variables, which may have prognostic implication.