A major problem in pulmonary sarcoidosis is the assessment of disease activity. We established a clinical score system composed of degree of dyspnea, chest radiographic stage, forced vital capacity, and clinical assessment of disease activity (normal = 0, maximum = 16). We evaluated this score in 50 patients with sarcoidosis along with other proposed measures of disease activity: bronchoalveolar lavage percent lymphocytes (% lymphs), Gallium-67 lung uptake measured as total lung to background ratio (TL/B ratio), and serum angiotensin converting enzyme (SACE) levels. The patients we studied had an average clinical score of 5.6 +/- 2.7 (+/- SD). Though bronchoalveolar lavage % lymphs (32 +/- 20%), TL/B ratio (192 +/- 73), and SACE (137 +/- 66) were all significantly elevated in these patients, Gallium-67 uptake was most frequently abnormal (80% of patients). However, the TL/B ratio was higher in smokers (231 +/- 91) than nonsmokers (178 +/- 64, p less than 0.05). There was no correlation between our clinical score, or any part of the clinical score, and other laboratory measures of alveolitis. Bronchoalveolar lavage % lymphs and TL/B ratio correlated weakly (n = 50, r = 0.36, p less than 0.02), while % lymphs and SACE correlated less well (n = 29, r = 0.36, p = 0.051). There was no correlation between TB/L ratio and SACE.(ABSTRACT TRUNCATED AT 250 WORDS)