Classification and immunodiagnosis of vasculitis: a new solution or promises unfulfilled?

For the clinician, the recognition and treatment of different types of the vasculitic syndromes are hampered by the absence of a satisfactory classification of vasculitis and the lack of diagnostic laboratory tests. Different approaches to formulating a classification of vasculitis include the practical, pathological and pathogenetic; and at different times all these approaches have been adopted, abandoned and revived. A combined clinicopathological classification of vasculitis with emphasis on the predominant size of vessels affected (Table 1) is recommended. Several immunodiagnostic tests of vasculitis have been described recently. These novel laboratory tools may shed new light on the pathogenesis of certain types of vasculitis, but as diagnostic tests they remain an unfulfilled expectation. The search continues.