[Activities and isozymes of adenosine deaminase and lactate dehydrogenase in tuberculous pleural effusion with special reference to the presence of mycobacterium tuberculosis].

We have previously shown that tuberculous pleurisy possesses a high level of adenosine deaminase (ADA) which is predominantly composed of ADA2. In this paper, we report the cases of tuberculous pleural effusion which contained mainly ADA1. In these cases, mycobacterium tuberculosis was positive by smear examination and/or culture and granulocytes were found to be major components. Analysis of lactate dehydrogenase (LDH) revealed that its activity was high and LDH5 occupied about 50% of total activity. In the tubercle bacillus negative cases, lymphocytes were the main components and the levels of LDH containing mostly LDH3 were low. It was assumed that the difference in LDH activity and isozyme pattern is due to the differential presence of leukocytes in pleurisy i.e., granulocytes and lymphocytes in tubercle bacillus positive and negative pleurisy, respectively. In conclusion, tuberculous pleural effusions can be divided into two groups on the basis of ADA and LDH activities and isozymes which may reflect the presence of mycobacterium tuberculosis.