ADA and empyema: Diagnostic thoracentesis showed that the CPPE/empyema group had significantly higher total cell count (TCC) (156,000±272,000 cells vs. 3,120±5,010 cells/μL; p<0.001), and levels of LDH (9,600±13,800 IU/L vs. 821±666 IU/L; p<0.001) and adenosine deaminase (ADA) (75.5±80.5 U/L vs. 28.6±23.0 U/L; p = 0.003) compared to the PPE group.