Epstein-Barr Virus (EBV)-Associated Pleural Effusions: Clinical Features, Cytomorphologic Characteristics, and Flow Cytometric Immunophenotyping
Hidehiro Takei, Dina Mody. Methodist Hospital, Houston, TX
Background: Pleural effusions (PEs) are frequently encountered specimens in cytopathology. Their etiology varies, and a percentage of PEs remain unexplained despite an intensive diagnostic workup. EBV is ubiquitous in the human population where it establishes lifelong latency after the initial infection. One previous study documented a 40% prevalence of EBV-DNA in unselected PEs. Our aim is to characterize the clinical and cytomorphologic features of EBV-associated PEs (EBV-PEs), which have not been previously described. Flow cytometric immunophenotyping was also performed for lymphocytic PEs.
Design: A database search was performed for PE cases with EBV-DNA identified in the fluid by real-time quantitative PCR in a period from 1/1/2007 to 8/30/2012. The corresponding fluid cytology and fluid chemistry data were reviewed, and the patients' demographic data and clinical features were recorded.
Results: A total of 20 cases (18 patients) of EBV-DNA positive PE were found, and all had corresponding cytology specimens. All PEs were exudates based on chemical analysis. All patients (13 males, 5 females; average age= 64.6 years) had a history of lung transplantation, and most presented clinically with shortness of breath during post transplant follow-up. 4 patients expired within 3 months following the thoracentesis. The median EBV-DNA level was 530 copies/mL (range: <100 – 248,300). Cytologically, lymphocytosis was present in 12 (60%) fluids, characterized by a polymorphous lymphoid population with variable numbers of reactive large lymphocytes. Scattered apoptotic lymphocytes and rare mitotic figures in lymphocytes were identified in 3 cases. Mesothelial cells varied in number and some cases showed reactive atypia. Flow cytometric analysis revealed no monoclonal population or aberrant T cell antigen expression. The lymphocytes were predominantly T cells with the CD4/CD8 ratio varying from 10:1 to 1:2 (reversed ratio).
Conclusions: Although rare, EBV-PEs can be seen in transplant patients. In the absence of an alternative diagnosis to explain the nature of the PEs in patients with a history of lung transplant, EBV-PEs should be included in the differential diagnosis especially when lymphocytosis is present in the fluid.
Monday, March 4, 2013 1:00 PM
Poster Session II # 76, Monday Afternoon