Abstract
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.
