Effects of oral cyclophosphamide and prednisolone therapy on the endothelial functions and clinical findings in patients with early diffuse systemic sclerosis

Abstract

Objective: The endothelial damage of microvascular structures in systemic sclerosis (SSc; scleroderma) is associated with increased levels of endothelial adhesion molecules and endothelium-associated cytokines, including E-selectin and thrombomodulin. Although there is still no ideal specific pharmacologic therapy for SSc, cyclophosphamide has resulted in clinical improvement in patients with SSc-related active alveolitis. This study was designed to assess the expression of E-selectin and thrombomodulin in patients with early diffuse SSc, and to investigate the effects of oral cyclophosphamide combined with prednisolone therapy on the levels of these endothelium-associated cytokines and on the patients' clinical outcomes.

Methods: Thirteen patients with early diffuse SSc were treated with oral cyclophosphamide (2-2.5 mg/kg/day) and methylprednisolone (30 mg/every other day) for 1 year. The outcomes were determined as clinical (skin score) and laboratory parameters (including the erythrocyte sedimentation rate, complete blood cell count, levels of C-reactive protein, antinuclear antibody, anti-double-stranded DNA, rate of creatinine clearance, and findings on pulmonary function tests, esophageal manometry, and echocardiography). The concentrations of E-selectin and thrombomodulin were measured in the pretreatment and posttreatment serum samples from the SSc patients and from 12 healthy adults as controls.

Results: In the patients with early diffuse SSc, pretreatment and posttreatment mean levels of E-selectin were 51 ng/ml (range 34.2-135.5) and 33.4 ng/ml (range 23-62.5), respectively (P = 0.01), and those of thrombomodulin were 82 ng/ml (range 35.8-120.5) and 74.6 ng/ml (range 23.3-91.3), respectively (P = 0.016). Clinical and laboratory parameters (the skin score and measures of pulmonary function [forced vital capacity and diffusing capacity for carbon monoxide]) were also improved (P < 0.05 for each) at the end of the followup period.

Conclusion: Combination therapy with cylophosphamide plus prednisolone is effective in the treatment of early diffuse SSc. Circulating levels of E-selectin and thrombomodulin not only demonstrate the extent of endothelial injury and/or activation, but also could be a useful marker to monitor the disease activity in SSc.