Thijsen S F T, Luderer R, van Gorp J M H, Oudejans S J G, Bossink A W J
Dept of Microbiology, Bosboomstraat 1, 3582 KE Utrecht, The Netherlands.
Eur Respir J. 2005 Oct;26(4):662-6. doi: 10.1183/09031936.05.00131204.
A high percentage of pleural effusions remain unexplained despite an intensive diagnostic workup. Epstein-Barr virus (EBV) infections occur worldwide and affect the majority of the population. The present study investigated the prevalence and clinical relevance of EBV in pleural effusions. A prospective study was performed in which 60 consecutive patients with pleural effusion were enrolled. Real-time quantitative EBV-PCR was performed on pleural fluid and serum. Pleural fluid was further evaluated using standard biochemical, cytological and microbiological procedures. Demographic data, medical history and medication were recorded. A total of 24 (40%), from 60 pleural fluids tested, were positive in the EBV-PCR. Median EBV-DNA levels for positive samples was 454 genome equivalents (geq).mL-1 (range 36-163,446 geq.mL-1). A total of 20 (59%) out of 34 unexplained pleural effusions were EBV-PCR positive. Serological analysis of all patients with a positive PCR revealed a previous infection. Patients with a positive EBV-PCR on pleural fluid were more likely to have a positive EBV-PCR on serum than patients with a negative PCR on pleural fluid. Epstein-Barr virus reactivation in pleural fluid is a frequent event and the absence of an alternative diagnosis to explain the nature of the effusion in the majority of cases suggests an aetiological role for Epstein-Barr virus in the development of pleural effusion.