The differential diagnosis value of the combined detection of ADA,CEA on benign and malignant pleural effusion

Objective To investigate the differential diagnosis value of the combined detection of adenosine deaminase(ADA)and carcinoembryonic antigen(CEA)on benign and malignant pleural effusion.Methods The activity of pleural fluid ADA was determined by performance rate method,and the content of pleural fluid CEA was tested by immunochemilu-minometric assay.Results 4 cases out of 63 patients with tuberculosis(TB) was tested positive for pleural fluid CEA,the positive rate was 6.3%;19 cases out of 24 patients with malignant pleural effusion was tested positive for CEA,the positive rate was 79.2%.The positive rate of pleural fluid CEA in malignant pleural effusion group was significantly higher than that of tuberculous pleural effusion with statistical difference(P0.01).The activities of ADA in tuberculous and malignant pleural effusion were(69.5±13.2)U/L and(13±6.3)U/L respectively.Taken the ADA40 U/L as the threshold for the diagnosis of tuberculosis,the positive rate was 73%(46/63).Conclusion Combined detection of pleural fluid ADA,CEA in tuberculous pleural effusion and malignant pleural effusions in the differential diagnosis has important clinical significance.