Influence of disease manifestation and antineutrophil cytoplasmic antibody titer on the response to pulse cyclophosphamide therapy in patients with wegener's granulomatosis

Objective. To assess the effectiveness of pulse cyclophosphamide (CYC) in the treatment of Wegener's granulomatosis (WG) and to identify the patients who are responsive to the treatment. Methods. The prospective study included 43 patients with biopsy‐proven WG. Clinical, radiographic, laboratory, and immunologic data were evaluated for predicitive values regarding the outcome of pulse CYC therapy. Results. Only 42% of the patients showed complete or partial remission that lasted at least 6 months after cessation of pulse CYC therapy. These responders had a higher frequency of disease activity limited to the upper and lower respiratory tract (39%, versus 8% in the nonresponder group; P < 0.05) and had lower titers of classic antineutrophil cytoplasmic antibody (cANCA) prior to treatment (<1:64 42%, versus 6% in the nonresponder group; P < 0.05). In the 58% of patients who did not respond to pulse CYC treatment, there was both systemic disease involving more than 4 organ systems (mainly, the heart, nervous system, eye, and skin) and constitutional symptoms. Serious side effects induced by pulse CYC occurred in only 1 patient. Conclusion. Based on these findings, pulse CYC therapy appears to be effective in WG patients with moderate disease activity and low titers of cANCA, but of little benefit in patients with severe WG. Pulse CYC should therefore not be used as first‐line therapy in patients with severe and rapidly progressing forms of WG associated with high titers of cANCA.