[The value of measuring adenosine deaminase activity in pericardial effusion fluid for diagnosing the etiology of pericardial effusion].

The diagnosis of tuberculous pericarditis is difficult. The cultures of the pericardial fluid for M.tuberculosis are often negative. The determination of ADA activity in pleural fluid in TB patients /PTS/ is very useful. It seemed reasonable to measure ADA activity in pericardial effusion. ADA activity in pericardial fluid of 40PTS/19 women and 21 men/with large pericardial effusion of different etiologies who were treated in our institute in years 1988-1995 was investigated. The median age was 44 years. In each case the pericardiocentesis was performed. PTS were grouped as follows: group I-4 PTS with strongly suspected TB pericarditis, group II-32 PTS with malignancy and group III-4 PTS with miscellaneous diseases. In group I the mean ADA activity was 24U/I(3-60), in group II 18U/I (3-60) and in group III 18U/I (0-37) (with a cutoff value for ADA activity of 40U/I). It was definitive bacteriologic diagnosis of TB pericarditis in PTS of group I. Our observation does not confirm the earlier data about the high ADA activity in clinically suspected TB pericarditis without bacteriologic diagnosis. The value of ADA determination in pericardial fluid is its high specificity (97%) in excluding of TB etiology of pericardial effusion.