Diagnostic approach to patients with suspected vasculitis.

Vasculitis presents several diagnostic challenges. Firstly, patients could present with protean clinical manifestations with a wide spectrum ranging from isolated cutaneous vasculitis to multisystem involvement. Secondly, there are several medical conditions that could mimic the presentation of vasculitis. The range of differential diagnosis is therefore broad. Thirdly, vasculitis could occur as a primary disorder or be secondary to various medical conditions. It becomes important to differentiate them, as treatment of some forms of vasculitis such as those that are secondary to infection or drugs, is different from that of primary vasculitis. Fourthly, there are several different forms of vasculitis. Some are benign and self limiting, while others have the potential to threaten vital organ function and life. It follows that a rational approach is required during evaluation of patients with suspected vasculitis.