Objective. To define the most effective treatment for severe polyarteritis nodosa (PAN) and Churg-Strauss syndrome (CSS) and to investigate the indication for plasma exchange treatment. Methods. We conducted a prospective, randomized, multicenter trial in which 62 patients were randomly assigned to receive either prednisone plus cyclophosphamide (intravenous bolus) (group A; n = 28) or prednisone plus cyclophosphamide (intravenous bolus) plus plasma exchanges (group B; n = 34) as first-line treatment for severe PAN or CSS. Factors predicting poor prognosis were renal symptoms, gastrointestinal tract involvement, cardiomyopathy, central nervous system involvement, weight loss >10% of body weight, and age >50 years old. Patients with hepatitis B virus-related PAN were not included in this study. The end point of the study was control of the disease (recovery or remission) or death. Results. Clinical symptoms and laboratory findings did not differ significantly in the 2 groups. Initial control of the disease was similar in both groups. Relapse after initial control of the disease was observed in 7 patients (4 in group A and 3 in group B). The mean +/- SD followup period was 31.1 +/- 20 months for group A and 35.9 +/- 16.8 months for group B. At 5 years of followup, 38 patients (61.3%) were cured (16 in group A and 22 in group B), and 5 (8.1%) were in remission without treatment but had not yet completed the cure-defining period of 18 months (3 in group A and 2 in group B), Eight (12.9%) (2 in group A and 6 in group B) were considered to be in clinical remission and required a maintenance regimen of low-dose corticosteroids. Eleven patients died during the study period (7 in group A [25%], 4 in group B [11.8%]). Uncontrolled vasculitis was responsible for 4 deaths (2 in each group), and treatment side effects caused the death of 1 patient in group A. There was no significant difference between the 5-year cumulative survival rates of the 2 groups (75% and 88%, respectively). Conclusion. Based on our data, combined treatment with prednisone, cyclophosphamide, and plasma exchanges is not superior to treatment with prednisone and cyclophophamide alone, and plasma exchanges should not be systematically proposed for initial treatment of severe PAN or CSS.
