Epstein-Barr Virus-Positive Pleural Effusion
A total of 20 cases (18 patients) of EBV-DNA–positive PE were found; patient demographics, clinical information, and laboratory data/pathologic findings are listed in Table 1. The patients were 13 men and 5 women with a mean age of 64.6 years. All patients had a history of lung transplant for various underlying lung diseases. The duration between transplantation and thoracentesis for pathologic examination varied from approximately 1 month to more than 10 years (median, approximately 3 months). The most common presenting symptom was shortness of breath. Chemical analysis demonstrated that all PEs were exudates. In 20 cases of PEs, 14 were considered "idiopathic," while six were most likely secondary to infection given the positive culture results (of the fluid or lung tissue) or a history of aspiration pneumonia.
The EBV load varied from below the limit of quantitation (75–99 copies/mL) to 248,300 copies/mL (median, 530 copies/mL). Two patients with an EBV load of 335 and 516 copies/mL (cases 10 and 20, respectively) died within 1 week after thoracentesis. Serum EBV load was tested on the same day of thoracentesis in three cases, one (case 16) of which showed no detection. One patient (case 19) had a pleural biopsy, which was performed 2 days after thoracentesis. EBV-encoded small nuclear RNA in situ hybridization was performed (Ventana Medical Systems, Tucson, AZ) and was negative.
The FCM study was performed in 13 cases. Ten cases were cytologically lymphocyte-rich PEs, and all fluids were shown to be T-cell predominant. No monoclonal B-cell population or aberrant T-cell antigen expression was noted in any PEs tested. The CD4 to CD8 ratio of T cells in PEs varied tremendously, from 10:1 to 3:20.
BAL was performed in nine cases, all of which showed no cytological abnormality present. TBBx was performed in 10 cases, and two cases showed minimal acute cellular rejection (A1) and one was pneumonia with culture positive for Klebsiella pneumoniae.
Of 20 cases, 19 cases (17 patients) had corresponding fluid cytology specimens for review. Cytologic findings are listed in Table 2. One of these 19 cases was unsatisfactory for cytologic evaluation due to insufficient cellularity (case 6); however, granulocyte predominance was found by FCM. Another case had no cytology slides available for review (case 13).
Cytologically, 13 PE specimens demonstrated lymphocytosis, characterized by a polymorphous lymphoid population Image 1, with varying numbers of large activated lymphocytes in three cases. One of these three cases was positive for vancomycin-resistant Enterococcus faecium in PE culture (case 17). Of those with lymphocytosis, rare lymphocytic mitosis was seen in three cases and scattered lymphocytic apoptosis was seen in three cases. Of these cases, one (case 11) showed abundant activated large lymphocytes with both mitotic and apoptotic figures, and malignant lymphoma was morphologically suspected as a differential diagnosis Image 2. The other three PEs exhibited a mixed inflammatory pattern with lymphocytes, neutrophils, and histiocytes, and two PEs showed abundant neutrophils (case 20 was consistent with a clinical diagnosis of empyema). There was no significant difference in EBV load between the fluids with lymphocytosis and those with mixed or neutrophilic inflammation (P = .3004, Mann-Whitney). All cases (except for one unsatisfactory case) contained various numbers of mesothelial cells, and three cases showed reactive atypia. In case 20 (with a history of aggressive skin cancer), mesothelial (reactive) atypia was so significant that a cytologic diagnosis of "suspicious for metastatic malignancy" was initially rendered for the pleural fluid Image 3.
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Image 1.
The most common feature of Epstein-Barr virus–positive pleural fluid with a lymphocyte-predominant pattern (Diff-Quik, ×400).
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Image 2.
Lymphocytosis with abundant large activated lymphocytes in Epstein-Barr virus–positive pleural fluid (case 11) (Diff-Quik, ×400).
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Image 3.
Neutrophil-predominant pleural fluid with scattered atypical mesothelial cells in a patient with a history of aggressive skin cancer (case 20) (Papanicolaou, ×400).
Results
A total of 20 cases (18 patients) of EBV-DNA–positive PE were found; patient demographics, clinical information, and laboratory data/pathologic findings are listed in Table 1. The patients were 13 men and 5 women with a mean age of 64.6 years. All patients had a history of lung transplant for various underlying lung diseases. The duration between transplantation and thoracentesis for pathologic examination varied from approximately 1 month to more than 10 years (median, approximately 3 months). The most common presenting symptom was shortness of breath. Chemical analysis demonstrated that all PEs were exudates. In 20 cases of PEs, 14 were considered "idiopathic," while six were most likely secondary to infection given the positive culture results (of the fluid or lung tissue) or a history of aspiration pneumonia.
The EBV load varied from below the limit of quantitation (75–99 copies/mL) to 248,300 copies/mL (median, 530 copies/mL). Two patients with an EBV load of 335 and 516 copies/mL (cases 10 and 20, respectively) died within 1 week after thoracentesis. Serum EBV load was tested on the same day of thoracentesis in three cases, one (case 16) of which showed no detection. One patient (case 19) had a pleural biopsy, which was performed 2 days after thoracentesis. EBV-encoded small nuclear RNA in situ hybridization was performed (Ventana Medical Systems, Tucson, AZ) and was negative.
The FCM study was performed in 13 cases. Ten cases were cytologically lymphocyte-rich PEs, and all fluids were shown to be T-cell predominant. No monoclonal B-cell population or aberrant T-cell antigen expression was noted in any PEs tested. The CD4 to CD8 ratio of T cells in PEs varied tremendously, from 10:1 to 3:20.
BAL was performed in nine cases, all of which showed no cytological abnormality present. TBBx was performed in 10 cases, and two cases showed minimal acute cellular rejection (A1) and one was pneumonia with culture positive for Klebsiella pneumoniae.
Of 20 cases, 19 cases (17 patients) had corresponding fluid cytology specimens for review. Cytologic findings are listed in Table 2. One of these 19 cases was unsatisfactory for cytologic evaluation due to insufficient cellularity (case 6); however, granulocyte predominance was found by FCM. Another case had no cytology slides available for review (case 13).
Cytologically, 13 PE specimens demonstrated lymphocytosis, characterized by a polymorphous lymphoid population Image 1, with varying numbers of large activated lymphocytes in three cases. One of these three cases was positive for vancomycin-resistant Enterococcus faecium in PE culture (case 17). Of those with lymphocytosis, rare lymphocytic mitosis was seen in three cases and scattered lymphocytic apoptosis was seen in three cases. Of these cases, one (case 11) showed abundant activated large lymphocytes with both mitotic and apoptotic figures, and malignant lymphoma was morphologically suspected as a differential diagnosis Image 2. The other three PEs exhibited a mixed inflammatory pattern with lymphocytes, neutrophils, and histiocytes, and two PEs showed abundant neutrophils (case 20 was consistent with a clinical diagnosis of empyema). There was no significant difference in EBV load between the fluids with lymphocytosis and those with mixed or neutrophilic inflammation (P = .3004, Mann-Whitney). All cases (except for one unsatisfactory case) contained various numbers of mesothelial cells, and three cases showed reactive atypia. In case 20 (with a history of aggressive skin cancer), mesothelial (reactive) atypia was so significant that a cytologic diagnosis of "suspicious for metastatic malignancy" was initially rendered for the pleural fluid Image 3.
(Enlarge Image)
Image 1.
The most common feature of Epstein-Barr virus–positive pleural fluid with a lymphocyte-predominant pattern (Diff-Quik, ×400).
(Enlarge Image)
Image 2.
Lymphocytosis with abundant large activated lymphocytes in Epstein-Barr virus–positive pleural fluid (case 11) (Diff-Quik, ×400).
(Enlarge Image)
Image 3.
Neutrophil-predominant pleural fluid with scattered atypical mesothelial cells in a patient with a history of aggressive skin cancer (case 20) (Papanicolaou, ×400).