Viral genomes in the pericardial fluid and in peri- and epicardial biopsies from a German cohort of patients with large to moderate pericardial effusions.

The aetiology of pericardial effusion has been generally assessed by clinical work-up only, which leaves a large cohort of patients with "idiopathic" effusions virtually undiagnosed. In accordance with the ESC guidelines, this contribution intends to change this attitude. After therapeutic or diagnostic pericardiocentesis of 259 patients with large to moderate pericardial effusions, pericardial fluid, epicardial and pericardial biopsies, and blood samples were analysed by PCR for cardiotropic microbial agents. Cytology, histology, immunohistology of tissue and fluids and laboratory tests were performed. Of the 259 patients, 35 % suffered from an autoreactive aetiology, 28 % suffered from a malignant and 14 % from an infectious cause. Investigating all samples by PCR, we identified viral genomes in 51 (19.7 %) patients, parvovirus B19 (B19 V) being identified in 25 and Epstein-Barr virus (EBV) in 19 cases. In patients with a sole infectious aetiology (n = 36), B19 V was detected in 21 and EBV in 10 cases. When differentiating with regard to the material investigated for the presence of cardiotropic viruses, parvovirus B19 was most often detected in the epicardium and EBV was most frequently detected in the pericardial fluid independent from the final diagnostic categorisation. Bacterial cultures including tests for tuberculosis were all negative. Molecular techniques improve sensitivity, specificity and diagnostic accuracy for the underlying aetiology in pericarditis patients with effusion. The identification of specific viral signatures will help to understand pathogenetic mechanisms in pericarditis and allow to tailor an adequate therapy beyond antiphlogistic treatment.