Adenosine deaminase activity in bronchoalveolar lavage fluid of sarcoidosis patients]

We studied adenosine deaminase (ADA) activity in bronchoalveolar lavage fluid (BALF) specimens from 24 patients with sarcoidosis. Mean BALF-ADA activity was significantly (p < 0.0001) elevated in patients with sarcoidosis (1.02 +/- 1.01 IU/L, mean +/- SD) compared to the subjects in a healthy control group (0.08 +/- 0.29 IU/L). In the sarcoidosis patients with high BALF-ADA activity (> or = 1.0 IU/L), AaDO2 was significantly (p < 0.0001) elevated compared to its level in patients with normal BALF-ADA activity (< 1.0 IU/L). BALF-ADA activity was significantly (p < 0.01) higher in patients who exhibited lung-field accumulations on 67Ga scintigrams compared to those with no accumulations, and significantly (p < 0.001) higher in patients undergoing corticosteroid treatment compared to in those patients who did not receive such treatment. These findings were similar to the results of studies using data on BALF-ADA/albumin ratios. Furthermore, they suggest that the localized production of ADA may increase in sarcoidosis patients displaying 67Ga scintigram lung-field accumulations with increased AaDO2, and that BALF-ADA activity may be a useful indicator of disease activity and the need for treatment.