The value of pulmonary function measurements in progressive systemic Sclerosis

Pulmonary function measurements were performed in 42 patients with progressive systemic sclerosis （PSS） to determine the value of pulmonary function test in patient with PSS. According to roentgenologic evidences of chest film, patients with PSS were divided into 3 groups, and the pulmonary function data were prepared between these 3 groups. Our results showed that DLco and small airway function may already be abnormal when roentgengraphy abnormality is absent in early stage of PSS. These tests become abnormal much earlier than the reduction of lung volume in subjects who had minimal dyspnea and roentgenologic change. Our study also suggests that measurements of DLco and small airway function may be the useful diagnostic markers in early stage of pulmonary impairment of PSS before the disease is clinically serious.