A new international classification of childhood vasculitis.

There has been, for many years, a need for an acceptable classification of childhood vasculitis as well as criteria for classifying specific sub-categories of vasculitic disease affecting the young. Hitherto, there has been, with certain exceptions, much reliance on adult classification systems and criteria that have not proved entirely satisfactory. A recent International Consensus Conference held in Vienna in June 2005 attempted to rectify this state of affairs. It resulted in a new proposal for childhood vasculitis classification and proposals of classification criteria for several important categories of childhood vasculitis including Henoch-Schonlein purpura, Kawasaki disease, polyarteritis nodosa (with additionally definitions for cutaneous and microscopic polyarteritis), Wegener granulomatosis and Takayasu arteritis. The process involved the Delphi technique to gather a wide spectrum of opinion from pediatric rheumatologists and nephrologists followed by the Consensus Conference attended by a group of pediatricians with extensive vasculitis experience where nominal group techniques were utilized to agree on a general classification and classification criteria for individual childhood vasculitides. The consensus that was reached will hopefully provide pediatricians with a valuable tool in the study of childhood vasculitides but will require appropriate validation using patient and control groups.