Lung function studies in diagnostics and follow-up of pulmonary sarcoidosis

摘要

In 66 patients the relationship between lung volumes and lung mechanics in pulmonary sarcoidosis was investigated. Lung volumes, static lung mechanics, lung resistance, dynamic lung mechanics and arterial blood gases at rest and during exercise were obtained. Fifteen functionally compromised patients received steroids during one year. They were re-investigated during the treatment and at a follow-up after an average of 7 years. In another 41 patients with newly diagnosed sarcoidosis, the kinetics of the lung clearance of (sup 99m)Tc-DTPA measured over 180 minutes was explored, and compared to kinetics in healthy smokers. The relationship between lung clearance and lung volumes, lung mechanics, arterial blood gases and disease activity assessed with serum angiotensin-converting enzyme and (sup 67)Ga scintigraphy was studied. Reducing lung volumes and compliance, increased resistance and arterial oxygen tension were common. Vital capacity (VC), and changes of VC at follow-up, corresponded to the slope of the static elastic pressure/volume curve, and to the variation of it. Other static lung volumes reflected rather the position of the curve along the volume axis. Reduced VC also reflected obstruction. Forced expiratory volume in one second revealed to equal extent lung stiffness and obstruction. Lung mechanics showed abnormalities not always evident from spirometry.In 50% of the patients lung clearance of (sup 99m)Tc-DTPA disclosed an abnormally fast mono-exponential clearance or a bi-exponential clearance, which however differed from that in smokers. Lung clearance more readily detected abnormal function than did spirometry. Clearance did nor correlate with other investigations. (sup 67)Ga lung activity was higher in patients with a pathologic lung clearance. (Atomindex citation 25:066768)