Evidence for protein oedema, neutrophil influx, and enhanced collagen production in lungs of patients with systemic sclerosis.

Bronchoalveolar lavage fluid from patients with systemic sclerosis was analysed for evidence of pulmonary vascular leakage, inflammatory cell influx, and enhanced type III collagen synthesis. Eighteen patients with systemic sclerosis and computed tomographic evidence of fibrosing alveolitis were compared with 16 patients with a normal scan. The albumin concentration in lavage fluid was higher in all patients than in normal volunteers. Patients with an abnormal computed tomogram as a group had increased proportions of all inflammatory cell types, whereas those with a normal scan had increased neutrophils only. Increased lavage type III procollagen peptides were found in all patients with an abnormal computed tomogram and eight of those with a normal scan. These results suggest that pulmonary vascular leakage and neutrophil influx may be early pathological features of lung disease in systemic sclerosis and frequently associated with enhanced collagen production. Thus lavage of patients with systemic sclerosis may identify lung inflammation and altered collagen metabolism early in the evolution of fibrosing alveolitis.