Leucocyte migration inhibition and rosette tests in pleural effusion.

Lymphocytes from pleural effusions have been examined with leucocyte migration inhibition tests (LMIT) and the numbers of B and T lymphocytes estimated. In cases of tuberculous pleurisy a positive LMIT was more frequent than in those of neoplastic etiology. In cases of other etiology no difference has been observed. The proportion of T lymphocytes in pleural effusions from patients with neoplasia was significantly higher (P < 0.01) than in other diseases. The number of B lymphocytes was also lower than in cases of other etiology (P < 0.01). The per cent distribution of T and B lymphocytes in tuberculous pleural effusion differed markedly from that of malignant etiology, in the former the proportion of B lymphocytes was high while that of T lymphocytes was low.