Combination therapy with corticosteroids, cyclosporin A, and intravenous pulse cyclophosphamide for acute/subacute interstitial pneumonia in patients with dermatomyositis

Objective. Acute/subacute interstitial pneumonia (A/SIP) in patients with polymyositis/dermatomyositis (PM/DM) is frequently fatal within months despite high dose prednisolone (PSL) therapy. Our objective was to improve the survival rate of patients with A/SIP associated with PM/DM; and to characterize patients with PM/DM who are at high risk of developing A/SIP. Methods. We conducted a pilot trial of combined immunosuppressive therapy with high dose PSL, 10-30 mg/kg of intravenous pulse cyclophosphamide (IVCYC) every 3-4 weeks, and 2-4 mg/kg/day of cyclosporin A (CSA) for patients with A/SIP. A/SIP was diagnosed based on a history of rapidly worsening respiratory symptoms, progressive radiological findings or hypoxemia, and compatible findings in high resolution computed tomography images. Results. Before December 2000, 12 patients with DM among 83 PM/DM patients developed A/SIP, and 9 patients died despite treatment using high dose PSL with or without a choice of CSA, cyclophosphamide, or azathioprine. Thereafter, 10 patients with DM among 27 PM/DM patients developed A/SIP, and they were given combination therapy with PSL, CSA, and IVCYC. Five patients survived and are doing well for more than 2 years, although the remaining 5 patients died of respiratory failure within 3 months. DM patients with A/SIP showed the following characteristic features: mild myositis, palmar papule, fever, and negative or low titer of antinuclear antibody. Conclusion. Immediate institution of intensified immunosuppressive therapy should be considered for patients with A/SIP complicating DM. However, even early recognition of A/SIP and immediate commencement of a regimen including CSA and IVCYC in addition to high dose PSL may not be sufficient for some of those patients.