Efficacy and limitations of pulse cyclophosphamide therapy in polymyositis and dermatomyositis.

OBJECTIVES

To assess the therapeutic response of intravenous (IV) pulse cyclophosphamide therapy in polymyositis and dermatomyositis.

METHODS

Data of 9 patients (M:F = 2:7) who received IV pulse cyclophosphamide therapy were retrospectively analyzed.

RESULTS

The mean symptom duration was 11.33 ± 10.6 months (range, 2-34 months). The cohort comprised (1) primary idiopathic polymyositis (n = 1), (2) primary idiopathic dermatomyositis (n = 1), (3) childhood type associated with vasculitis (n = 1), and (4) associated with collagen vascular disease (n = 6). All patients improved and became clinically asymptomatic after a mean period of 12.33 ± 6.5 months (range, 4-24 months); 5 remained asymptomatic at the end of a median follow-up period of 22 months. All patients received concomitant steroid therapy, and in 6, steroids could be tapered after the initiation of IV pulse cyclophosphamide therapy.

CONCLUSIONS

In this cohort of polymyositis/dermatomyositis, treatment with IV pulse cyclophosphamide was associated with improvement; the therapeutic response was sustained in majority of the patients.