Increased pulmonary clearance of aerosolized 99Tcm-DTPA in patients with a subset of stage I sarcoidosis

Abstract

Measurement of the pulmonary clearance of aerosolized 99Tcm-diethylenetriamine pentaacetate (99Tcm-DTPA) as a marker of pulmonary parenchymal damage was performed in 10 non-smokers with sarcoidosis, none of whom was on medication, and the results compared with 12 normal controls. Posterior images were obtained using a single-headed gamma camera, with the subjects in a supine position, for 30 min after inhalation of aerosolized 99Tcm-DTPA had ceased. The pulmonary clearance of 99Tcm-DTPA was significantly increased in the sarcoidosis patients (57.6 +/- 22.1 min in the right lung, 62.2 +/- 22.7 min in the left lung) compared with the controls (79.3 +/- 10.2 and 78.4 +/- 7.7 min in the right and left lungs, respectively) (P < 0.05). Six of the 10 patients with sarcoidosis showed levels of pulmonary clearance, in both the right and left lungs, below the 95.5% confidence limit (mean +/- 2 S.D.) for the controls. Increased pulmonary clearance of 99Tcm-DTPA was also found in 2 of 4 patients with stage I sarcoidosis. No relationship was found between the pulmonary clearance of 99Tcm-DPTA and inflammatory markers (ACE, lysozyme) in the serum.