Standardized quantitative 67Ga scintigraphy in relation to carbon monoxide diffusion capacity in pulmonary...

67Ga lung uptake, obtained by a standardized computer-assisted quantitative method of 67Ga scintigraphy, was compared to carbon monoxide diffusion capacity (DLCO) in 45 patients with biopsy proven pulmonary sarcoidosis. Increased 67Ga lung uptake was found in 24 (53%) patients and DLCO was decreased in only 16 (36%) patients. An inverse relationship (r = -0.53; p < 0.001) was demonstrated between 67Ga lung uptake and DLCO. Eleven patients had an increased 67Ga lung uptake whereas the DLCO values were normal. There was no correlation between 67Ga lung uptake or DLCO and either chest radiographic stage or mode of clinical presentation. On the basis of the normal limits for 67Ga lung uptake and DLCO, 4 subgroups of patients could be identified. The use of the combined investigations may open an opportunity for an early identification of those patients who require therapy. An increased 67Ga accumulation within the lung seems to be considered as a factor indicating risk for pulmonary disability, which is supported by the follow-up of the 4 subgroups of patients.