[The indices of the humoral immunity and cytogram in pleural exudates of different etiologies].

A cytological and immunological examination of pleural exudates of different etiology indicates that tumour exudates differed from exudates of tuberculous and parapneumonic etiology by distinctly reduced level of immunoglobulin A as well as by an elevated content of circulating immune complexes. Prevalence of mesothelial cells accompanied by an increase of immunological indices in tumour exudates and their reduction in exudates in cases of cardiac pathology is to be considered as an unfavourable prognostic sign.