Cytokine activation in pericardial fluids in different forms of pericarditis

There are many causes of pericardial effusion and it is useful to classify them etiologically, since this disorder is the most common pathologic process involving the pericardium. This report details our experience with pericardioscopy and epicardial biopsy in 101 patients with pericardial effusions in whom pericardioscopy was performed. By means of clinical data and polymerase chain reaction we tried to elucidate the etiology of the pericardial effusion which were classified as follows: we found 41 effusions to be induced by primary malignant tumors or tumors metastatic to the pericardium. Specific diagnosis of viral and bacterial pericarditis was established in 17 patients by examination of the pericardial effusion with PCR, where we found 3 patients positive for adenovirus, 5 patients positive for cytomegalovirus, 2 patients positive for enterovirus-RNA and 5 patients positive for borrelia Burgdorferi-DNA. Additionally, idiopathic effusions (lymphocytic and autoreactive) were seen in 35 patients. In summary immunological and molecular biology investigations seem to provide an additional tool in the diagnostic of pericardial effusion with unknown etiology. If we focus on the ELISA results, there is some evidence, that the demonstration of activation markers and soluble mediators of inflammation such as Il-6, Il-8 and IFN-gamma in pericardial effusion and the simultaneously lack of these mediators in sera of the patients first may be helpful in the discrimination of autoreactive and lymphocytic effusion. Second, this cytokine pattern or distribution indicates a possible local inflammatory process, where these cytokines were all released from activated T lymphocytes present in lymphocytic effusion. In the future, this may have therapeutic implications.