Improved pulmonary function in systemic sclerosis after treatment with cyclophosphamide

Abstract

Pulmonary fibrosis is a common feature of systemic sclerosis (SSc) and a major cause of morbidity and mortality. Since alveolitis may be an essential step in the development of pulmonary fibrosis, we investigated the use of immunosuppressive drug therapy to improve pulmonary function in patients with SSc. Eighteen patients with progressive pulmonary dysfunction, diminished vital capacity (VC), and/or decreased static lung compliance (Cst) were treated with cyclophosphamide and corticosteroids for 1 year. Eight patients had diffuse cutaneous SSc and 10 had limited cutaneous SSc. The median disease duration was 2.5 years (range 0.5-17 years). VC increased in 14 of 18 patients and the median VC rose from 74% to 80% of predicted. Cst improved in 8 of 12 patients and the median Cst increased from 59% to 66% of predicted. Pulmonary nonfibrotic opacities disappeared in 9 of 12 patients. The erythrocyte sedimentation rate (ESR) and serum concentrations of orosomucoid, C-reactive protein, and aminopropeptide type III collagen all improved. The patients were divided into 2 groups based on the presence or absence of elevations in acute-phase protein levels and ESR before therapy. Among the 12 patients with biochemical signs of inflammation, VC increased in 11, and Cst improved or was unchanged in 7 of the 8 who were tested. The median VC in this subgroup increased from 73% to 80% of predicted and the median Cst increased from 57% to 60% of predicted. In the group of 18 patients overall, the skin score decreased, while esophageal and renal function remained stable. Cyclophosphamide may have a beneficial effect on pulmonary fibrosis in patients with SSc and elevated levels of acute-phase proteins. Controlled trials of cyclophosphamide in pulmonary SSc should be performed and should focus on such patients.